# Full Frame and Bigger Pixels vs. APS-C and Smaller Pixels - The Reach War



## jrista (Aug 9, 2014)

Well, I said for a long time that once I got a 5D III, I'd do some comparison shots. I've long held the opinion that crop sensor cameras, like the 7D, do have value in certain circumstances. The most significant use case where a camera like the 7D really shows it's edge over full frame cameras is in reach-limited situations. A reach limited situation is one in which you cannot get physically closer to your subject, and your subject does not fill the frame. The likely case is that you are using your longest lens, and will likely crop in post. 

In the past, others have made the argument that a camera like the 5D III or 1D X has so much more image quality than a camera like the 7D that the 7D could never compare. The argument was made that an upsampled 5D III or 1D X image (or even, for that matter, D800/E, D600, etc. image) would be just as good. 

I'd like to prove my case. I've taken the most reach-limited scenario possible...photographing the moon, with a 1200mm lens (Canon EF 600mm f/4 L II w/ Canon EF 2x TC III). I used a Canon EOS 7D and a Canon EOS 5D Mark III for imaging. The lens and camera were attached to an Orion Atlas EQ-G equatorial tracking mount, operating in Lunar tracking mode, to minimize any other factors that might affect image quality. Seeing (atmospheric turbulence measure) was average. 







Above is a GIF image of the 7D and 5D III images scaled to the same size, overlaid directly on top of each other using Photoshop's layer difference blending mode for best possible alignment. Both images were created exactly the same way, by initially focusing with BackyardEOS' focus module for optimum focus (BYEOS is like having a 2560x1600 live view screen...it's awesome!) The image exposures for both cameras are *1/100s f/8 ISO 200*. Five images for both cameras were taken, the best frame from each set was chosen for comparison. Both images were maximally cropped simply by choosing 1:1 in Lightroom. Both images had identical processing applied in Lightroom (one image was processed, it's settings were copied and pasted onto the other.) Both images were initially scaled to approximately 1/4 their original size (770x770 pixels, to be exact). 

The 5D III image was then layered onto the 7D image, and upsampled in Photoshop by a scale factor of exactly 161.32359522807342533660887502944%. This scale factor was derived by computing the sensor diagonals of both cameras:


```
ffDiag = SQRT(36^2 + 24^2) = 43.266615305567871517430655209646
apscDiag = SQRT(22.3^2 + 14.9^2) = 26.819768828235637870277777227866
```

Then dividing the FF diagonal over the APS-C diagonal:


```
43.266615305567871517430655209646/26.819768828235637870277777227866 = 1.6132359522807342533660887502944x
```

Then finally multiplying by 100% (to get a relative scale factor that I could directly apply with Photoshop's layer scaling tool.)

I believe the GIF above speaks for itself. The larger pixel size of the 5D III clearly does not resolve as much detail as the 7D does. Not only is the 7D image sharper, but there is a significant increase in fine details, small craters, nuances of color, etc. Here is another GIF, this time the images are only 1/2 original size (any larger, and the effects of seeing diminish any real benefit...I've had days where seeing is excellent, and more detail can be resolved, but sadly tonight was not one of those days):






The 7D's smaller pixels, despite being a generation prior to the 5D III's, are still resolving more detail, especially fine edges to crater rims (some of which don't even show up at all in the FF image), and are extracting a finer and more nuanced level of color. Many smaller craters, especially those that are inside larger craters, as well as the central mounds of many craters, are either difficult to make out or simply don't appear in the 5D III image, where as they show up clearly in the 7D image.

A common reach-limited use case is bird photography. Similar to the moon, it can be difficult to get close to and fully extract all the detail from a small songbird, shorebirds, and shy waders or waterfowl. One either needs a significantly longer lens on the full frame (I am still experimenting with the 5D III, but I'll probably be using 840mm and 1200mm a lot more than 600mm), or you need the skill to get much closer to your subjects, in order to fully take advantage of the benefits the larger frame has to offer. 

Anyway, there you have it. The 5D III is an excellent camera, and when you have the option of framing identically (i.e. filling the frame with your subject), the larger frame trounces the 7D in terms of image quality. It gathers 2.6002949408613476991603214253469x more light:


```
(36 * 24) / (22.3 * 14.9) = 864 / 332.27 =  2.6002949408613476991603214253469
```

With more than two and a half times more light, it's two and a half times better. Like using two and a half stops lower ISO on the cropped sensor. However if you don't have the option of either getting closer to your subject, or using a super long lens (not everyone has the option of spending $13,800 ($12,800+$500+$500) on a 600mm f/4 II and both of Canon's Mark III TCs), then there is no question that a camera like the 7D, or currently the better option the 70D, is going to give you the option of creating more detailed photos. 

*UPDATES:*

Ok, here are a few updates, as per requested.

The first image here is the 7D and 5D III at "native" size. To further clarify my procedure from above. These images were "cropped", however they were cropped such that 100% of the sensor height was used. The only parts of the image that were discarded were the empty black sky areas to the left and right of the moon. That means, from a technical standpoint, these are 1:1 crops. They are then downsampled, but since I used 100% of the sensor height, these crops are directly indicative of the relative size difference of the moon in both frames.






You'll notice the 5D III image is sharp. Both images were sharp, or at least, as sharp as I could get them. I basically used a live view method of focusing, however one that is much more advanced. I used the program BackyardEOS, which is an astrophotography imaging tool that is specifically designed for Canon EOS cameras (which are endemic in the astrophotography world for budget imagers...the T3, T3i, 60Da and 6D are pretty much the top cameras you'll find in astrophotographers kits...those that don't use dedicated astrophotography CCDs.) 






BYEOS has a brilliant frame and focus wizard. It takes the live view feed from the camera, and renders it on a computer screen. I can maximize the program and basically get 2560x1600 live view (minus a bit program panels and border). 

I use these tools to focus:






I use coarse and medium to get focus close, then step with fine. The fine focusing arrows are extremely fine...they are designed to focus stars, so they move the focus group in the lens by the smallest possible amount. I spent about five minutes with these tools with both cameras to find the best focus possible. It isn't as easy as it sounds...you don't just end up with a crisp, sharp moon. The moon, at that size, looks more like it was dropped into a vat of boiling water, and every few seconds you have a moment where the "water" (atmospheric turbulence or "seeing") clears, and in that moment you have to gauge whether to focus forward or back to get it better.

So, the images are focused as best as I could get them.

The next image here is a noise comparison. It has three frames...a 7D crop that is unscaled, a 5D III crop that is unscaled, and a 7D crop that mirrors the 5D III crop that IS scaled. The 7D, at native size, definitely has more noise. It also looks almost as soft as the 5D III image.






When the 7D image is downsampled to the same size as the 5D III image...any advantage the 5D III had in terms of noise disappears. The 7D image clears up a bit, and appears a little sharper. Fine details pop a little bit more than they do with the 5D III. 

Why? Because the moon covered the *same absolute sensor area*. There is a difference in pixel count between the two images, but overall, *both sensors gathered exactly the same amount of light!* _That's the key there._ There is no advantage to a larger sensor if you are not utilizing that increase in sensor area. If your using the same exact absolute sensor area between both cameras...there is no difference. If the 7D had 6.25µm pixels, then the two cameras, in this kind of situation, _would perform IDENTICALLY_.

In a reach-limited scenario, you want smaller pixels. It really doesn't matter if your using a full frame sensor, a medium format sensor, a micro 4/3rds sensor, or an APS-C sensor. If the pixels are all the same size, and you put the same number of pixels on your subject...assuming all four of those sensors use the same technology, there is literally no difference. That is usually not the case, though. Smaller sensors generally tend to use smaller pixels. The 7D still has smaller pixels than the D800 and D810. Smaller pixels trump bigger pixels when you are reach-limited.


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## grimson (Aug 9, 2014)

Thank you for this excellent comparison. Nice to see 'proof' whatever the comparisons may be.


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## Skulker (Aug 9, 2014)

It's very interesting to see the effort you have gone to to make the comparison. Clearly you have made quite an effort. 

When I got the 1Dx I had a 7D. As a wildlife photographer I expected to keep the 7D2 as a backup. I very quickly realised it wasn't goingto get used. And as a back up I wanted the smaller camera, the 1Dx is heavy to lug aaround. so i sold the 7D and got a 5D3. I have no regrets 

so I'm in the "your milage may vary camp on this one". For me and my photography the so called crop factor is out weighed by the improved IQ at higher ISO and when not cropping the images need less PP.

give me the 5D3 over the 7D any day.


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## sanj (Aug 9, 2014)

Thank you for taking the effort. 

Am not convinced yet. There seems to be loop holes. I cannot put my finger on it yet. Will study this and post again.

In any case this will be an eye opener.


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## Valvebounce (Aug 9, 2014)

Hi Jrista. 
I'd just like to add my thank you for this post, it is people like yourself taking the time and effort to do scientifically relevant tests like this that makes this such a great forum, with reliable accurate answers to questions. 
It is posts like this that enable people like me to know that I can rely on the info, I can see the calculations, and even though I might have to look up a term like "seeing" and may not have used my maths enough to remember how to do the ratios, I can tell the method was sound. 
So thank you for this. 

Cheers Graham.


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## MichaelHodges (Aug 9, 2014)

Jrista,

Do you think you could post the unprocessed RAW files? I'd like to see these with no noise reduction. It almost looks like the 5DIII had too much applied or was out of focus.


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## dtaylor (Aug 9, 2014)

jrista - thank you for posting your test.

I've found that most of the time a FF file cropped to APS-C yields about the same IQ as an actual APS-C in prints up to 20", given your typical "reach limited" subject matter (sports, birds, etc.).

However...the minute you have to crop even further into both files the sharpness and detail differences you observed in your test come into play. I've made 20" prints from 8-9 MP crops out of 7D files that remained sharp and fairly detailed. I could not crop into a 5D2 or 5D3 file for the same magnification and make a satisfactory print.

Of course if you can fill the frame then the 5D3 sensor is better. But if you need the reach in decent light...


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## 100 (Aug 9, 2014)

Nice comparison. Thanks for posting. 
They were both shot with the same settings and the same processing in Lightroom and I wonder what happens if you use the best settings and most optimal processing for each camera/image. 



jrista said:


> With more than two and a half times more light, it's two and a half times better. Like using two and a half stops lower ISO on the cropped sensor.



Double the light is one stop so 2.6 times the light is about one and a quarter stops.


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## Northstar (Aug 9, 2014)

Jrista...thanks for taking the time to do this comparison, it's informative and helpful!

Could you post the two photos without upsampling the 5d3 image. I'd like to see the 5d3 image cropped to match the 7d without the upsampling process.

Thanks again,
North


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## lol (Aug 9, 2014)

I can agree with jrista's example, as two of my biggest photography interests are wildlife and astrophotography. If you are reach limited and want more resolution, you simply need all the pixels density you can get. Upsampling a single image can't restore that lost information. The only way a bigger sensor can compete is to stick a bigger optic on the front to offset that. For most of us, there is a point where practicality and cost dictate a limit to how big we go. The other way bigger sensors could compete is to have comparable pixel sizes. I would love a hypothetical 46MP sensor in a full frame body, as that would roughly match the pixel density of APS-C. Then you get the best of both worlds. But until Canon bring out an affordable equivalent to the D810, I'm not holding my breath on that one and will look forward to what the 7D mk2 brings.

As a special case, multiple low resolution images can used to reconstruct higher resolution images! This can and is used in astrophotography where the subjects don't tend to change much, but obviously is useless for wildlife. In essence, you need to move the camera slightly between shots, so the low resolution image is not made up of exactly the same scene. Fractional pixel shifts will do to get you that sub pixel information.


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## sagittariansrock (Aug 9, 2014)

Northstar said:


> Jrista...thanks for taking the time to do this comparison, it's informative and helpful!
> 
> Could you post the two photos without upsampling the 5d3 image. I'd like to see the 5d3 image cropped to match the 7d without the upsampling process.
> 
> ...



+1. 
I would also like to see the original images compared, with the 5D image only cropped to the size of the 7D image, positioned appropriately. 
Thanks.


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## neuroanatomist (Aug 9, 2014)

Thanks for the comparison!

As I've often stated, APS-C does have a 'reach advantage'...if you're FL limited AND at low ISO (~800 or less) AND printing larger than 16x24"/A2. 

Something else I'm curious about...how small is too small? For your moon shots, would a 16-18 MP m4/3 body via adapter yield more detail than your 7D? How about an SX50 HS (granted, not the same lens - but AlanF has posted some provocative comparisons). 

Moon shots aside, I'm not convinced of the advantages for bird photography, for several reasons. If I'd need to crop an image too deeply, I would just delete the shot (more likely, not have taken it). With the shutter speeds needed, ISO often needs to be raised beyond the tipping point, where the greater noise of APS-C means less detail. Those are sensor-based factors, and as I've also often stated, we don't take pictures with bare silicon sensors. Many people have reported that the AF of the 5DIII yields a higher keeper rate than the 7D, and a higher keeper yield of in-focus shots despite the lower frame rate (and with the 1D X, both rate and yield are higher).

I appreciate the careful testing in the specific situation you describe. I'd be very interested to hear, after you've used the 5DIII to shoot birds for a while, how frequently you grab the 7D for that purpose, instead. Like Skulker, I kept my 7D for a while...and didn't use it, so eventually sold it (and for far more than it would fetch today, with 7D prices dropping like a stone). 

Despite the 'reach advantage' held by APS-C in certain specific scenarios, IMO the main advantage of APS-C is not reach, but lower cost.


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## lol (Aug 9, 2014)

Which has greater noise? An APS-C sensor or a full frame sensor cropped to APS-C size? Bare in mind our hypothetical situation is you're still reach limited, so the bigger sensor in itself conveys no advantage, and the only arguable difference is pixel size. For roughly comparable sensor generations I'd argue they're practically the same. Outside of lab tests, it probably isn't significant.

At ISO6400, I'd happily use either of my 600D or a 5D mk2 (as secondary body to 7D), but when reach limited the 600D would be my preference of the two. To me noise isn't the limiting factor in this scenario.


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## Lee Jay (Aug 9, 2014)

lol said:


> Which has greater noise? An APS-C sensor or a full frame sensor cropped to APS-C size? Bare in mind our hypothetical situation is you're still reach limited, so the bigger sensor in itself conveys no advantage, and the only arguable difference is pixel size. For roughly comparable sensor generations I'd argue they're practically the same.



Correct.


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## Click (Aug 9, 2014)

Very interesting post Jon. Thank you for taking the time to do this comparison.


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## neuroanatomist (Aug 9, 2014)

lol said:


> Which has greater noise? An APS-C sensor or a full frame sensor cropped to APS-C size? Bare in mind our hypothetical situation is you're still reach limited, so the bigger sensor in itself conveys no advantage, and the only arguable difference is pixel size. For roughly comparable sensor generations I'd argue they're practically the same. Outside of lab tests, it probably isn't significant.
> 
> At ISO6400, I'd happily use either of my 600D or a 5D mk2 (as secondary body to 7D), but when reach limited the 600D would be my preference of the two. To me noise isn't the limiting factor in this scenario.



Below are a pair of images shown at 100%. One is from an 18 MP APS-C camera at *ISO 3200*. The other is from an 18 MP FF camera at *ISO 6400*, a full stop higher than the APS-C image. 

I'm having trouble telling which is which, the noise levels are so similar. : :


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## dak723 (Aug 9, 2014)

jrista said:


> Both images were initially scaled to approximately 1/4 their original size (770x770 pixels, to be exact).
> 
> The 5D III image was then layered onto the 7D image, and upsampled in Photoshop by a scale factor of exactly 161.32359522807342533660887502944%. This scale factor was derived by computing the sensor diagonals of both cameras:



Perhaps I am misunderstanding your method - so forgive me if I am. But doesn't cropping each image the same amount and then upsampling negate the actual comparison? To get the same approximate image with the two cameras, shouldn't the FF be cropped more to get the moon to be the same size on the image. Upsampling seems a rather unreliable method to get a fair comparison.

In other words, if you used the entire shot for the 7d, your image is 5184 x 3456 pixels. The same approximate composition on the 5D3 would be cropped to approx. 3600 x 2400 (1.6 crop factor). Those images are the ones that I would like to see compared with no resampling done. 

Again, forgive me if I have misunderstood your method.

And I agree with your basic premise that a crop factor camera - because of its longer reach - can be advantageous. If not for image quality, then definitely for getting a closer view through the viewfinder to get the shot you want, both to better see your subject and also to get the exact composition you want. When I switched from crop to FF, I was very disappointed in my inability to get more reach with my max 300mm zoom. There was no way I could afford a 480mm or greater lens - and the size would be a big issue. I ended up buying an Olympus Em-1 (M4/3) with their 75-300mm lens - giving me the equivalent of 600mm max zoom. Sure, there are downsides when it comes to noise, etc., but I am happier with the results from the crop camera with extra reach than I was with the FF camera.


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## fishprof (Aug 9, 2014)

jrista

Thank you very much for this post. It is exactly the kind of comparison I have been hoping to see. The ASP-C with greater "reach" works for me in the kinds of photography that interest me. I don't have the funds to buy big glass. Even if I did, I don't have the physical strength to tote a 600mm around all day. Your analysis convinces me to upgrade to a 7DII (whenever?) instead of a 5DIII. If the 7DII offers better high ISO performance than the 7D, I'll be one happy camper.


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## neuroanatomist (Aug 9, 2014)

dak723 said:


> jrista said:
> 
> 
> > Both images were initially scaled to approximately 1/4 their original size (770x770 pixels, to be exact).
> ...



Some upsampling would be required, but yes...I think you've exposed a potential problem with Jon's comparison. You'd need to upsample a bit, to compensate for the 5DIII's 23 MP vs the 7D's 18 MP. Structuring the test so that you are using upsampling to compensate for the 1.6x crop factor (which appears to be what Jon has done), instead cropping the FF image to the APS-C FoV and upsampling to compensate for the much smaller MP differential, would seem to bias the comparison to favor the smaller sensor. 

When I compared my 7D to my 1D X no upsampling was needed, since both start as 18 MP images, so cropping the FF image to the APS-C FoV yields images that are directly comparable. 

When performing a comparison like this, choices must be made. Using upsampling to compensate for the 1.6x crop factor means the resulting images have the same MP count. Is that necessary? Cropping an image from a current Canon FF sensor to the APS-C FoV yields a 7-8.6 MP image. If that's sufficient for your intended output (and 7-8 MP is sufficient for 16x24" prints), then there's no need to upsample. If you _do_ need to upsample, there are better ways to do it than a straight 160% resize in Photoshop as Jon did (which adds even a little more bias in favor of the 7D in Jon's comparison).


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## Dylan777 (Aug 9, 2014)

I recently picked up 2x TC III for more reach with my 400mm f2.8 IS II. IQ drops 20-30%. FF body has larger pixel plus cropping will make it worst.


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## ajfotofilmagem (Aug 9, 2014)

Thank you for your test. He shows that APS-C may give better results in situations of limited reach and low ISO. For me it was not a surprise, because I've thought that way. I also know that if the comparison was made ​​in ISO6400, the result would be different. But this does not invalidate the test result in ISO200. 

Another reason to love APS-C is price and weight of the lenses. Those who have held in their hands 7D + 300mm F4L and also 1Dx + 500mm F4L (angle of view equivalent), know that the weight and price are very different. Yes, I know I have high noise in 7D ISO6400, but we hope that 7D Mark ii will close this gap.


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## MichaelHodges (Aug 9, 2014)

neuroanatomist said:


> lol said:
> 
> 
> > Which has greater noise? An APS-C sensor or a full frame sensor cropped to APS-C size? Bare in mind our hypothetical situation is you're still reach limited, so the bigger sensor in itself conveys no advantage, and the only arguable difference is pixel size. For roughly comparable sensor generations I'd argue they're practically the same. Outside of lab tests, it probably isn't significant.
> ...




One of those crops smells like a 7D.

I shoot wildlife all over the country. Most of the big animals come out in crepuscular conditions. At this point, noise will determine which camera you use. Going from 420mm to 300mm doesn't matter because you won't get the shot with APS-C.


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## ScottyP (Aug 9, 2014)

neuroanatomist said:


> lol said:
> 
> 
> > Which has greater noise? An APS-C sensor or a full frame sensor cropped to APS-C size? Bare in mind our hypothetical situation is you're still reach limited, so the bigger sensor in itself conveys no advantage, and the only arguable difference is pixel size. For roughly comparable sensor generations I'd argue they're practically the same. Outside of lab tests, it probably isn't significant.
> ...



I'm not convinced. I'd need to see the squirrels on the moon to be sure.


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## Skulker (Aug 9, 2014)

Dylan777 said:


> I recently picked up 2x TC III for more reach with my 400mm f2.8 IS II. IQ drops 20-30%. FF body has larger pixel plus cropping will make it worst.



I'm not sure how you are measuring or quantifying your "IQ drops 20-30%" but if I was you I would be looking hard at what is wrong. I use a 2X TC III with a 300mm f2.8 IS II and I have used it with an equivalent 400. I'd like to see anyone reliably tell if a TC has been used or not.


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## LetTheRightLensIn (Aug 9, 2014)

neuroanatomist said:


> Thanks for the comparison!
> 
> As I've often stated, APS-C does have a 'reach advantage'...if you're FL limited AND at low ISO (~800 or less) AND printing larger than 16x24"/A2.



First, I don't think it makes sense to mention printing size. If you are very reach limited you might only have enough left to fill 2MP. It really depends. Maybe you have 1MP or maybe 15MP, it depends shot to shot. And 16x24" is pretty large, even a complete frame from a 5D3 only fills 13x19" at 300PPI!

Second, you can go above ISO800 and still get a reach advantage from the 7D. In fact, with a high contrast subject in a well lit portion of the frame, the advantage is actually still clear even at ISO6400. In fact, compared to the 5D2, the 7D does the same, or almost always better, in any circumstance at any ISO, if reach limited (as the 7D has higher pixel density, is more efficient per area of sensor and has better high iso banding characteristics). Compared to the 5D3 it is a bit trickier, but I have shots of Hairy Woodpeckers (granted that is a high contrast target), so-called real world, where the 7D does better IMO and they were ISO1600-2500, better with ease. Of course if you have a low contrast main subject and it's dark in coloration and in a dark part of the frame, in that case, the 7D may fall back to the 5D3 or even fall behind it at higher ISOs since the 5D3 is a little bit more efficient per sensor area and has good high iso banding characteristics.


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## scyrene (Aug 9, 2014)

jrista said:


> Well, I said for a long time that once I got a 5D III, I'd do some comparison shots. I've long held the opinion that crop sensor cameras, like the 7D, do have value in certain circumstances. The most significant use case where a camera like the 7D really shows it's edge over full frame cameras is in reach-limited situations. A reach limited situation is one in which you cannot get physically closer to your subject, and your subject does not fill the frame. The likely case is that you are using your longest lens, and will likely crop in post.
> 
> In the past, others have made the argument that a camera like the 5D III or 1D X has so much more image quality than a camera like the 7D that the 7D could never compare. The argument was made that an upsampled 5D III or 1D X image (or even, for that matter, D800/E, D600, etc. image) would be just as good.
> 
> ...



Very effective presentation. I did the same thing when I got my 5DIII - although in that case, I was comparing it to the 50D (see https://flic.kr/p/cHKKfQ). Still, I gave the crop sensor the edge. I didn't think to overlay them, but instead (if I recall correctly) compared the size of the smallest visible features each could resolve.

Can the full frame camera regain some ground through image stacking? It certainly seems to produce much crisper images.


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## johnhenry (Aug 9, 2014)

Its really great to see someone has done a really good comparison between the two big players from Canons two formats


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## Sella174 (Aug 9, 2014)

Well, if the lens is up to the job, obviously any high megapixel count sensor at a low ISO setting will provide more image detail than a bigger sensor with a lower megapixel count at the same ISO setting with the same lens.


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## jrista (Aug 9, 2014)

jrista said:


> Both images were initially scaled to approximately 1/4 their original size (770x770 pixels, to be exact).
> 
> The 5D III image was then layered onto the 7D image, and upsampled in Photoshop by a scale factor of exactly 161.32359522807342533660887502944%. This scale factor was derived by computing the sensor diagonals of both cameras:



That would give an unfair advantage to the 5D III. You have to do exactly the same things to both images to keep both results consistent. Even if I did not crop at all, the 5D III image would still have to be upscaled by the same amount. 

I performed every action identically, for both the 1/4 scale and 1/2 scale images, then added the one extra step of upscaling the 5D III moon to the size of the 7D moon. That was simply to normalize subject size. 

I can do it again, and leave everything at 100% scale. The moon in the 5D III shot is MUCH smaller than the moon in the 7D shot, so it really doesn't matter if I scale first or not. Here is another example...these are cropped and scaled to 770px, but the 5D III image was not upscaled...it's at it's native size:






For reference, these are full size crops...the full height of the sensor is used...I only cropped out empty black space to the left and right. For all intents and purposes, these are downsampled 1:1's. I'll get some more images of them at 100% size, without any noise reduction.


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## neuroanatomist (Aug 9, 2014)

LetTheRightLensIn said:


> neuroanatomist said:
> 
> 
> > Thanks for the comparison!
> ...



To your first point, as I stated originally, if I would need to crop so severely that I would be left with a 1-2 MP image, I wouldn't bother pressing the shutter button.

To your second point, the squirrels above tell a different story. Granted, I've not done a head to head of 7D vs. 5DIII, but the 1D X cropped down to match framing is clearly superior to the 7D at higher ISO settings.


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## jrista (Aug 9, 2014)

MichaelHodges said:


> Jrista,
> 
> Do you think you could post the unprocessed RAW files? I'd like to see these with no noise reduction. It almost looks like the 5DIII had too much applied or was out of focus.



I'll post some 100% size crops (no scaling) so you guys can see the noise. 

Regarding the foucs...that is actually the impact of seeing. As I described in my original post, with a longer focal length, you can kind of "cut through" that a bit more. Maybe that is skewing the results a little...but remember that both images are suffering from the effects of seeing, not just the 5D III. The 5D III suffers a little more from seeing, however I did choose the best out of five of both the 5D III and 7D images. 

The thing about seeing is there are moments when the turbulence "flattens", and things get really clear. There is actually an astrophotography technique, used even by professional observatories, called "Lucky Imaging". Described in 1978 by David L. Fried, the technique involves taking many (sometimes many thousands) of exposures of the same celestial subject in sequence. Over the span of those exposures, many will have near-perfect seeing, and the subject will show up clearly. Professional observatories might use highly sensitive imagers to take tens of thousands of short exposures of a single subject, then pick the best 500 and integrate those to get extremely clear results that rival Hubble images (which does not suffer from seeing at all, given it's in space). Now, I did not take thousands of exposures. 

Something I can certainly try is to set up on a better night with better moon features, and take several hundred each with both cameras, and pick the best out of those frames. That is a much more significant task, however I'm happy to do it if it would help further prove the point. I do not believe it will change the results. There are 2.6x more pixels in the area of the moon for the 7D than the 5D III. If we have 3 million pixels on subject with the 5D III, we are going to have 7.8 million pixels on subject with the 7D.

It really doesn't matter either way...the 7D is ultimately going to win the detail battle when your reach is limited. I'll share more images, and I'll see if I can get the RAWs uploaded somewhere so you guys can experiment yourself.


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## LetTheRightLensIn (Aug 9, 2014)

I'm not surprised. It's been shown again and again before, but some just don't want to believe. I did careful tests and posted them, Romy has done the same, but some still insisted the 7D just can't compare, even when reach limited, not even to the 5D2. In fact, on FM right now, there is a group still insisting that the 7D isn't as good even when reach limited, considering that, it's welcome to have yet another demonstration.

Here is a quick shot I dug up from my low ISO, high-contrast target test, pretty darn clear to me the 7D has better reach. It goes 7D on top, then 5D2, then 5D3, then the 7D again. I've posted this here a few times in the past, but it never hurts to post it again, since no matter how many times such tests get posted, you constantly see threads pop up where people claim the 5D2/5D3 easily do better than the 7D even when reach limited:

Make sure to click the image to get the 100% view!


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## jrista (Aug 9, 2014)

100 said:


> Nice comparison. Thanks for posting.
> They were both shot with the same settings and the same processing in Lightroom and I wonder what happens if you use the best settings and most optimal processing for each camera/image.
> 
> 
> ...



You are correct about the number of stops. My mistake.

As for settings...what would be better settings? I mean, exposure is exposure...and technically speaking, using the same ISO means the 5D III has the advantage, no? I used ISO 200 for both shots...the larger pixels of the 5D III should mean that much more light is gathered per pixel at ISO 200 (which is indeed the case, noise comparison coming.) 

So, I honestly don't think I could have used any better settings on the 5D III. And exposure is exposure...it's light over time...for a given subject of given brightness, you have to use the same exposure.


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## LetTheRightLensIn (Aug 9, 2014)

MichaelHodges said:


> I shoot wildlife all over the country. Most of the big animals come out in crepuscular conditions. At this point, noise will determine which camera you use. .... you won't get the shot with APS-C.



You won't?? Even if you use say a 7D and a 5D2 and the 7D sensor is more efficient at collecting and converting photons per area of surface than the 5D2?? With the 7D you can chose to get either: more detail (unless conditions are super bad) and more noise OR slightly better detail with less de-bayer and other artifacts and slightly better noise (if you view or convert to same scale as the 5D2).


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## unfocused (Aug 9, 2014)

Thanks for the disciplined comparison. 

This is one reason why I think the 7DII will be Canon's "high megapixel" camera (probably at about 24 mp). 

It makes sense to me that Canon will optimize its top of the line APS-C camera to emphasize the strengths of its format -- which is resolution. They will then have full frame bodies optimized for noise and crop frames optimized for resolution and reach. 

It's also why I can't imagine a 7DII with less megapixels than the current 7D or 70D – people who want lower noise at higher ISOs, have the 6D. Which will be in the same price bracket as the 7DII (or possibly even slightly less.)

Fits in nicely with Canon's two-body marketing strategy.


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## jrista (Aug 9, 2014)

neuroanatomist said:


> lol said:
> 
> 
> > Which has greater noise? An APS-C sensor or a full frame sensor cropped to APS-C size? Bare in mind our hypothetical situation is you're still reach limited, so the bigger sensor in itself conveys no advantage, and the only arguable difference is pixel size. For roughly comparable sensor generations I'd argue they're practically the same. Outside of lab tests, it probably isn't significant.
> ...



I think the 7D can do even better than your example. Here is a bird photographed with a 500mm f/4 L II:






Very low noise. Here is another: 






Also very low noise. The 7D, when used properly, can be a truly superb camera. I think people get caught up in the noise levels when they first use it, then make a decision early on that the 7D simply cannot produce low noise results. 

I'm a very well versed guy when it comes to photography. I do not have pro-level skill and my images don't exhibit pro-level quality, but that is simply a matter of practice. I still have to work, and I work my butt off to pay for the kind of equipment I buy. I know what the difference between the 5D III and 7D is. I've had more than enough time with the 5D III, between playing with other peoples out in the field, to having had mine for several months now. Things are what they are...6.25µm pixels vs. 4.3µm pixels. Smaller pixels mean more detail. Greater sensor area on subject means more light. Normally, a full frame sensor is capable of putting MORE sensor area on subject...however that is not the case in a reach-limited scenario. In a reach limited scenario, the same sensor area is on subject. That means the only significant difference is pixel size.

I've said it so many times, I know others have also said it. Noise is relative to the area, not the pixel. If two cameras use the exact same area of sensor to resolve a subject, then there is no difference in noise. Not when the image from the sensor with smaller pixels is downsampled to the same dimensions as the image from the sensor with bigger pixels.


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## LetTheRightLensIn (Aug 9, 2014)

neuroanatomist said:


> LetTheRightLensIn said:
> 
> 
> > neuroanatomist said:
> ...



Hey 2MP still looks nice shared on the web, plus it doesn't have to be 2MP, it could be 6MP or 8MP or whatnot and, as I said, even 23MP still doesn't make 16x24" hit 300PPI!



> To your second point, the squirrels above tell a different story. Granted, I've not done a head to head of 7D vs. 5DIII, but the 1D X cropped down to match framing is clearly superior to the 7D at higher ISO settings.



The squirrels tell me no story. 

1. the processing is pretty terrible IMO. NR city, no way to tell what is going on, all smeary and waxy looking, looks almost OOF for both and yet still with some nasty pepper noise. I can't compare noise or detail there the processing is so weird and who knows if applied evenly either.

2. If it gets to the point that someone finds the noise too bothersome to care about the reach advantage then you normalize and compare at the same scale and since the 7D average de-bayer mistakes and so on over more pixels and you get effectively downsampled res those aspects come out at least a trace in the 7D's favor and then as for noise, it depends upon the bodies, as I said the 7D has better noise per sensor area than many FF cameras (although it's a bit worse than the 5D3 and a bit more so still compared to the 1DX) and better high iso banding characteristics than any Canon FF other than 6D/5D3/1DX, all the 1Ds3,1Ds2,1Ds,5D2,5D have worse.


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## jrista (Aug 9, 2014)

Alrighty. I've updated the original post with more examples. I've added full 1:1 crop comparisons between the 7D and 5D III, WITHOUT scaling the 5D III. That should clearly show how much smaller in the frame the moon is with the 5D III, at exactly the same focal length.

I've also added a noise comparison example, which shows both images at native size, then downsamples a 7D of the same region to 5D III dimensions.


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## LetTheRightLensIn (Aug 9, 2014)

jrista said:


> I've said it so many times, I know others have also said it. Noise is relative to the area, not the pixel. If two cameras use the exact same area of sensor to resolve a subject, then there is no difference in noise. Not when the image from the sensor with smaller pixels is downsampled to the same dimensions as the image from the sensor with bigger pixels.



So then why do you keep questioning DxO sensor normalization? What you just described above is exactly the same thing. So why do you get it in one context, but not in the DxO context?


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## jrista (Aug 9, 2014)

LetTheRightLensIn said:


> jrista said:
> 
> 
> > I've said it so many times, I know others have also said it. Noise is relative to the area, not the pixel. If two cameras use the exact same area of sensor to resolve a subject, then there is no difference in noise. Not when the image from the sensor with smaller pixels is downsampled to the same dimensions as the image from the sensor with bigger pixels.
> ...



We've had this argument. We've had it countless times. You know the answer. I've been extremely detailed and clear about my opinions, and exactly what my opinions are. I'm NOT going to let you ruin this thread by diving into another pointless discussion of DXO. You want to have that debate, please, don't ruin my thread...start another thread. PLEASE. 

Everyone, let's keep DXO out of this discussion. This thread has nothing to do with comparing Canon and Nikon cameras or anything like that. It has to do with the reach advantage of smaller pixels. That's it. I don't want this thread to be derailed by another useless debate that we've all had ten thousand times.


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## RustyTheGeek (Aug 9, 2014)

Lots of stuff to digest on this thread. I have to admit that I eventually started skimming a bit.

Fortunately, I think the general consensus supports what I have always thought about this subject.

At the end of the day, the fact that I don't have to put forth the effort to crop images in post when I use a APS-C sensor camera is well worth owning that body, IMHO. After all, when shooting hundreds of swimming pictures, I already have enough work to do with the lighting issues.


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## Dylan777 (Aug 9, 2014)

Skulker said:


> Dylan777 said:
> 
> 
> > I recently picked up 2x TC III for more reach with my 400mm f2.8 IS II. IQ drops 20-30%. FF body has larger pixel plus cropping will make it worst.
> ...



20-30% is my own est. IQ drops. No scientific data.

With 1.4x TC III, IQ still good(not good as bare). The IQ drops dramatically with x2 TC III, especially in Ai servo.

IQ will drop when use with TC, on any lenses. I don't care how good the 300mm f2.8 IS II is. If you don't see IQ drops on your 300 when use with 2x TC, then you might want to check your 300 as bare.


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## Steve (Aug 9, 2014)

jrista said:


> I think the 7D can do even better than your example. Here is a bird photographed with a 500mm f/4 L II:
> 
> 
> 
> ...



Whats the EXIF on these? They both look like they were shot with flash so I'm guessing they are low ISO shots. 

There seems to be this idea that there are a lot of people who think the 7D (or crop sensor cameras in general) is useless or bad when I don't think that's the case at all. The 7D can be used to make really excellent pictures, no doubt about it. It's a fantastic camera and it clearly has some advantages in some very, very specific situations. But there is a reason that pros use full frame camera bodies and there is a reason that Canon and Nikon have made their highest end, action specific, pro level cameras full frame. Its just plainly more useful in more shooting situations to have the better noise handling and IQ of the FF sensor. I mean, the 7D might have the advantage for low ISO moonshots but those are going to make up a tiny percentage of shooting situations compared to, say, early morning/late evening wildlife or indoor/night sports shooting. You can literally get useful shots at 12k ISO on a 5DIII/1DX while the 7D starts falling apart at 1600. There's also the matter of the AF systems and the whole "who cares how many pixels you can put on a blurry subject?" thing  Hopefully the 7DII will eliminate that difference but for the time being its also a legit concern.


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## Skulker (Aug 9, 2014)

jrista said:


> ............
> I've long held the opinion that crop sensor cameras, like the 7D, do have value in certain circumstances. The most significant use case where a camera like the 7D really shows it's edge over full frame cameras is in reach-limited situations.
> 
> ............
> ...



While I agree with you that a 7D (or any so called crop sensor) can have advantages over a so called full frame sensor. I think you need to review your work if your objective is to reach a valid conclusion.

1) you start off with a strong opinion. (its better to have an open mind)
2) Then you try to "prove my point". (it might be better to try to test your opinion)
3) Then you do something that is going to be very detrimental to one of the images.

You may claim that you would have to upsample the 5D3 image to get the same size as the 7D. But you have already down sampled it - so you have lost detail in the 5D3 file.

To demonstrate I made a simple file in Photoshop. 770 pixies ;D wide, copied it, scaled it to 481 wide, then upscaled it to 770 wide. Hardly by chance my file had two types of detail. A sharp line and a not so sharp line. The result can be seen below.

I think I have just proved that photoshop is better than photoshop.  

Don't get me wrong I'm a fan of the 7D and think its a great camera. I also think there is a place for "crop sensors". I'm waiting for the 7D2, I don't think it will be for me, but I definitely see a crop sensor shaped hole in my kit.

and finally whats with 30 odd decimal places!


EDIT: Just in case anyone wonders ;D the down sampling and up sampling were done with default PS settings


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## candc (Aug 9, 2014)

jrista said:


> neuroanatomist said:
> 
> 
> > lol said:
> ...



Very nice bird photos.I know this has been hotly debated here but I am pretty sure its the pixel size and not the sensor area that affects noise the most. My reasoning is that I have looked at images from the d800 which has aps-c size pixels and exhibits aps-c levels of noise when viewed on a per pixel basis. That tells me that pixels of a similar size in the same generation show similar noise levels?


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## Skulker (Aug 9, 2014)

Dylan777 said:


> Skulker said:
> 
> 
> > Dylan777 said:
> ...



LOL well put ;D

I'm quite happy with the quality of the 300 bare. and I'd agree there is a drop in IQ with both converters. I certainly wouldn't say it was anything like 20-30%. When I had the 7D I seldom used the 2x with the 300, but now I have the 1Dx its my favorite lens. I mean I use the 300 with 2x more than any other lens or combination. Maybe its something to do with the improved focusing on the latest cameras getting the best out of the lens and TC combination.


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## DominoDude (Aug 9, 2014)

You guys are never boring! As long as you reason with logic and use mathematical formula, then I don't care too much if you're wright or rong - we get to know how you are thinking to get to your results. I love it! It makes me think a bit too.
So keep 'em coming.


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## jrista (Aug 9, 2014)

candc said:


> Very nice bird photos.I know this has been hotly debated here but I am pretty sure its the pixel size and not the sensor area that affects noise the most. My reasoning is that I have looked at images from the d800 which has aps-c size pixels and exhibits aps-c levels of noise when viewed on a per pixel basis. That tells me that pixels of a similar size in the same generation show similar noise levels?



Your talking about on a per-pixel basis. On a per-pixel basis, that is true. However I'm talking about on a whole-image basis, or as it's called, on a "normalized" basis. When you compare images as a whole at the same size, assuming the same absolute area of sensor was used, then there won't be any difference in noise regardless of pixel size. There will, however, be a difference in detail.

This all assumes same pixel generation. The 5D III does have an advantage in upsampling due to it's newer pixel generation. It has higher quantum efficiency and overall a better pixel architecture, than the 7D pixels. That means less noise per pixel. I actually wish I had a 70D. That would make for a better comparison, as then both cameras would use sensors of similar generation, instead of being separated by over three years of technology. That's unlikely to happen unless I meet someone with a 70D who will let me borrow it for a night, though...as I have no intention of buying a 70D.


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## SiliconVoid (Aug 9, 2014)

Commendations on the in-depth research and comparison of the 7D and 5DmkIII.

Although the example used could be a little misleading as your results do not exactly show how APS-C sensors 'will' have a reach advantage over 35mm frame sensors - but exactly how they 'could' such as a 7D at 18mp over something like the 5Dmkx at 22mp when using the same lens for the same subject at the same distance. As APS-C sensors with less than half the pixel resolution of 35mm sensors still exist, and will likely be the case as long as the same technology is applied in both sensor designs, the ideology that APS-C will provide an advantage depends entirely on the mp/mm ratio of both sensors - not simply APS-C over full frame.

For example in Canon world (1.6 multiplier) something like the 7D would only provide the reach advantage you show as long as the smaller sensor provides at least 40% of the pixel count of the larger sensor. In other words, an 18mp APS-C sensor would have no reach advantage over a full frame 45mp sensor, because they would both produce the same resolution/data of the subject to crop for final output. Further, if the smaller sensor provided less than half the pixel count (less than 40% in the case of Canon) it would have no advantage at all as the larger sensor would have more pixels across the subject - both before and after cropping.

For some the mathematics may be difficult to follow as Canon does not have anything even close to 45mp (not even half that currently) so we can use another brand like Nikon. The 12mp APS-C sensor of say the D300s, or the 16mp APS-C sensor of the D7000, provide no reach advantage over their 36mp FX bodies because even with the subject only covering a ~50% region of the sensor it is still resolved by more mp than the APS-C sensors.

Still a very informative research project within the offerings of one manufacturer where a photographer has the choice of an APS-C body providing more than 40-50% of the pixel count of full frame.


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## jrista (Aug 9, 2014)

Skulker said:


> jrista said:
> 
> 
> > ............
> ...



You are correct. However, the image below was actually done a bit differently. In this case, both samples were downscaled to fit in the 770x770 pixel image...the 5D III image was not first downsampled then upsampled again. 






Your right, certainly not as stark a difference as my first example. Maybe that one is invalid. This example, however, does show that the 7D is still picking up more subtle details and nuances of color. The differences are not stark, but they do exist. Also note, both of these images were denoised. They were both denoised to the point where they both exhibited about the same noise levels...where noise was pretty much not visible. Obviously, there was quite a bit less noise reduction applied to the 5D III image.. That actually costs the 7D a little bit of it's detail as well...but it is on a level playing field with the 5D III as far as noise goes, so I still think it's a fair example.


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## jrista (Aug 9, 2014)

SiliconVoid said:


> Commendations on the in-depth research and comparison of the 7D and 5DmkIII.
> 
> Although the title could be a little misleading as your results do not exactly show how APS-C sensors have a reach advantage over 35mm frame sensors - but exactly how a 7D at 18mp can have a reach advantage over something like the 5Dmkx at 22mp when using the same lens for the same subject at the same distance. As APS-C sensors with less than half the pixel resolution of 35mm sensors still exist, and will likely be the case as long as the same technology is applied in both sensor designs, the ideology that APS-C will provide an advantage depends entirely on the mp/mm ratio of both sensors - not simply APS-C over full frame.
> 
> ...



You are correct, this is really less of APS-C vs. FF as it is small pixels vs. large pixels. It really doesn't matter if the small pixels are in an APS-C sensor or a full frame sensor...they could all be in an MFD sensor. The actual size of the frame really doesn't matter. What matters is the size of the pixel. It just so happens that smaller sensors *tend to have* smaller pixels...so it still holds true that APS-C sensors have reach advantages over FF sensors. 

The exact advantage is indeed relative to the specific sensors involved. The 7D probably wouldn't show any advantage over a D800 if they were compared like the image in my last post. The D800 has vastly superior sensor technology, so even though it's pixels are slightly larger, all that technology is going to trounce the 7D. The difference between the 7D and 1D X is going to be more significant than the difference demonstrated here between the 5D III and the 7D. That's a given, I think everyone understands that. 

I'd just been asked in the past to prove my case with actual images, instead of just theory and math, as I've often argued that the smaller pixels will always have a resolving power advantage over larger pixels. I am simply trying to fulfill my promise here, and provide some actual images to back up my claims. The advantage isn't wildly huge...I've never claimed that. It's a nuanced advantage, for sure. But the advantage exists, nevertheless. 

BTW, you brought up some differences between some older Nikon cameras and the new 36mp FF cameras. I'd like to point out that you failed to account for Nikon's newer APS-C parts. Nikon has several 24mp APS-C cameras that maintain the balance, and preserve the reach advantage of the smaller sensors over larger sensors. A 24mp Nikon APS-C is going to have a similar reach advantage over a 36.3mp D800 or D810. Both the smaller and larger sensors use the same technology, same generation of sensor...so the only key difference is pixel size. Assuming the subject fills the same absolute sensor area...on a normalized basis, the differences in noise will be minor but the differences in detail will be measurable.


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## candc (Aug 9, 2014)

jrista said:


> candc said:
> 
> 
> > Very nice bird photos.I know this has been hotly debated here but I am pretty sure its the pixel size and not the sensor area that affects noise the most. My reasoning is that I have looked at images from the d800 which has aps-c size pixels and exhibits aps-c levels of noise when viewed on a per pixel basis. That tells me that pixels of a similar size in the same generation show similar noise levels?
> ...



seems reasonable. 

your moon photos are always a pleasure to view. it is going to be passing a bit closer than usual so hopefully the the air is clear and dry so you can get some good shots.


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## jrista (Aug 9, 2014)

candc said:


> jrista said:
> 
> 
> > candc said:
> ...



I probably won't be imaging the moon this weekend. I think it will be cloudy, but even if it was not...the full moon just doesn't have the same kind of interesting detail as non-full moons do. There is no shadow playing across it's surface, so a LOT of small details are invisible.

That's actually a problem with my current set of images here...you can only see detail right around the limb, and there still isn't that much there. A waxing moon is actually better, as there are a lot of interesting features when it's going from the waxing crescent phase to just about where waxing gibbous begins. I am going to start imaging the moon regularly with the 5D III and 7D at 840mm and 1200mm (and maybe even 1680mm, as I still have my Kenko TC), and maybe I'll catch it on a good night with very good seeing, so atmospheric turbulence won't be as much of a problem as it was in this set of images.


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## SiliconVoid (Aug 10, 2014)

That is a good point, regarding current tech versus older tech, though my reference to the same 'technology' being used was in the context of technology limitations. In that at some point we will reach the boundaries of our technology where we are limited to xx number of pixels per mm. At which point APS-C sensors will not have any more than half the pixel count (40% for Canon) of full frame sensors and cropping becomes nothing more than an output/framing preference.

You and I will likely not see that day, but someone will..


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## neuroanatomist (Aug 10, 2014)

jrista said:


> ...certainly not as stark a difference as my first example. Maybe that one is invalid. This example, however, does show that the 7D is still picking up more subtle details and nuances of color. The differences are not stark, but they do exist.



Thanks. This revision addresses the issue about which dak723 and I were commenting (namely, a method biased in favor of the 7D). The difference you're showing here aligns more closely with what I've seen under similar conditions, i.e., at low ISO. I wonder what you'd find empirically at ISO 1600 or ISO 6400...


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## candc (Aug 10, 2014)

jrista said:


> candc said:
> 
> 
> > jrista said:
> ...



i know what you mean. its been hazy here and not very clear at night lately. the full moon is flat looking to begin with. the 2 shots below are 70d on the left and 6d on the right. the 6d one looks better but that is because i jacked up the contrast more on it. if they were processed the same i think the 70d one would look better. both were handheld with a sigma 120-300 and canon 2xiii taken a few minutes apart. i am going to keep an eye on the sky and see if i can get some better ones.


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## jrista (Aug 10, 2014)

neuroanatomist said:


> jrista said:
> 
> 
> > ...certainly not as stark a difference as my first example. Maybe that one is invalid. This example, however, does show that the 7D is still picking up more subtle details and nuances of color. The differences are not stark, but they do exist.
> ...



I dunno, I guess I can try. The moon has a LOT of dynamic range. In general, a hell of a lot more dynamic range than is possible to capture even with 14 stops of DR. So I try to shoot at as low an ISO as possible. On a Canon camera, ISO 100-400 are roughly the same, there is only a fraction of a stop difference in DR between them. I chose ISO 200 in this case, as I noticed that banding was occurring at ISO 400 on the 7D.

At ISO 1600 and 6400, the biggest single problem would simply be not having enough dynamic range to differentiate fine nuances of detail, due to quantization noise. That is one area where bigger pixels do help...they reduce quantization noise, so shadow detail is better at higher ISO.

You can't think of photographing the moon as photographing something in the dark, though. It's reflecting the sun. It is an EXTREMELY bright subject, and it has massive dynamic range. (I mean, think about it...how many stops of DR do you think you would need to resolve clean, crisp detail on the dark side while simultaneously resolving clean, crisp detail in the brightest crater hotspots on the light side? At least 20 stops...although, I've tried merging a bunch of moon frames together into a 32-bit float HDR for processing in ACR...and the shadowed site was STILL too noisy...)


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## RustyTheGeek (Aug 10, 2014)

*I think this thread has a lot of DR! So much that my head is starting to hurt! *


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## mackguyver (Aug 10, 2014)

Jon, thank you for the comparison and I'm not too surprised by the results. I found it to be that way when I shot with the 7D & 5DIII side-by-side, but as soon as you hit ISO 1600 (maybe even 800) or above, the reach advantage fell apart. Also, I found the Zone AF on the 7D to work well with AI Servo, but it wasn't nearly as good as the 5DIII. I kept them both for a while, but like many others, sold it, keeping the 5DII and 5DIII, at least until the 1D X replaced the 5DII earlier this year.


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## jrista (Aug 10, 2014)

So, I thought I'd throw in a bit of a "reference image". One way to image more detail, even when seeing is bad, is to take a lot of frames at high shutter speeds, and integrate the best 10-20%. It's called Lucky Imaging (lucky, in that in some of the frames you image, you'll be "lucky" enough to have very good to perfect seeing, where the turbulence clears and everything resolves at high resolution. The exposure duration can range anywhere from a few hundred milliseconds to microseconds. In my case, I kept my exposure settings, so my exposure duration was 10ms.

I took a couple of videos of the shadowed limb of the moon at 1000 frames at 5x zoom, and integrated the best 10% (100 frames) with AutoStakkert! 2. I used the 3x Drizzle option, which is actually a superresolution algorithm, then downsampled to 50% (1.5x original resolution), so the final image is actually showing detail beyond the diffraction and aberration limits of the optics. This is the result:




(Click for full size)

I want to give this a try with the 600mm, 2x TC, and 1.4x Kenko (1680mm) on the 7D. I bet I could resolve some pretty amazing detail by resolving a few thousand frames and integrating the best 10%.


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## jrista (Aug 10, 2014)

mackguyver said:


> Jon, thank you for the comparison and I'm not too surprised by the results. I found it to be that way when I shot with the 7D & 5DIII side-by-side, but as soon as you hit ISO 1600 (maybe even 800) or above, the reach advantage fell apart. Also, I found the Zone AF on the 7D to work well with AI Servo, but it wasn't nearly as good as the 5DIII. I kept them both for a while, but like many others, sold it, keeping the 5DII and 5DIII, at least until the 1D X replaced the 5DII earlier this year.



Yeah, at higher ISO, the 5D III's newer technology and larger pixels will certainly start to show their advantage. I don't think it would be a contest at ISO 6400...but as I mentioned to Neuro, your really starting to gimp yourself with the moon, because it's such a bright subject. 

I think a different test subject would be necessary to compare at high ISO. Something terrestrial, stationary, in lower light, that would really show the differences. The 7D does indeed fall apart above ISO 1600, and I don't think it would be able to keep up with the 5D III. However, I don't think the 5D III would be all that great either, as again...same absolute area. 

The advantage of a full frame is it's total light gathering capacity. When you normalize subject framing, rather than subject area, THAT is when the larger frame really starts to distance itself from APS-C. For example, this photo, which is nearly a 100% crop (I think I did a little rotation and cropped out part of the top of the frame), was shot with the 5D III at ISO 12800 in the dimmer light after the sun had fully set (one of my very first photos shot with the 5D III):







I applied very minimal NR, and processing, so it could actually end up looking even better than this. Same goes for this image (shot at the same time): 






When you have the opportunity of filling the frame, bigger is better. Technology still matters, and if the 7D II has vastly improved technology, the gap between it and the 5D III when the subject fills the frame will narrow, but it is highly doubtful that even the 7D II, if it moves to a 180nm process, gets a pixel count boost, gets better dynamic range, and overall better IQ...it is still unlikely that it would produce the same kind of IQ as a 5D III or 1D X or D800 or any other full frame camera.


----------



## neuroanatomist (Aug 10, 2014)

jrista said:


> neuroanatomist said:
> 
> 
> > jrista said:
> ...



The issues you describe make sense. However, in your original post you made the following point:

_A common reach-limited use case is bird photography. Similar to the moon, it can be difficult to get close to and fully extract all the detail from a small songbird, shorebirds, and shy waders or waterfowl._

I believe that bird photography is a much more common reach-limited use case than lunar photography. It would be useful to establish how applicable a demonstration of the 'reach advantage' in lunar photography is to bird photography, which comprises a broader range of conditions, frequently including subjects far less bright and/or a need for high shutter speeds. 

Do you find that in general bird photography has the same demands as lunar photography in terms of DR? What fraction of your bird images are taken at ISO 200? A look at my bird collection shows that the median for the library is ISO 1600. 

Regardless of demonstrated broad applicability to bird photography as a use case, your efforts with the moon shots are certainly appreciated!


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## jrista (Aug 10, 2014)

neuroanatomist said:


> jrista said:
> 
> 
> > neuroanatomist said:
> ...



I agree, the moon is not the same as birds. It's simply that it is a perfect reach-limited subject that doesn't zip around, constantly on the move (well, it moves, but I can track it). 

Regarding birds and DR...to be honest, I have not found that dynamic range is the issue when photographing birds. Not in the sense that I've ever come across a scene where I really felt the scene contained considerably more dynamic range than my sensor could handle, even at high ISO. Usually, my bird photography is between ISO 400 and 1600, however there have been times when I've really pushed the ISO, and still gotten great results (even with the 7D...such as the Black-Crowned Night Heron photo I've shared a few times.)

One of the things I always strive for in my bird photography is getting the right angles. The right angle from me to the bird, the right angles between the bird, myself, and the sun, and the right angle of the bird's head to it's body. Those are actually very critical aspects of bird photography. When you get the right angles, then the subject is usually fully illuminated (even if it's overcast, the light still primarily comes from a certain direction) and because your angle to the bird avoids any major DR swings (i.e. having half the bird in light and half the bird on dark shadow, such as when the sun is off to your left or right, rather than behind you over one of your shoulders), even at ISO 6400 you still usually have enough dynamic range to capture the subject without issues. 

There have been a few occasions when I've photographed dark birds with small very light colored spots (i.e. Belted Duck) or light birds with very dark parts (i.e. Bufflehead) where I am sometimes forced to use a lower ISO (which, to me, is probably ISO 800, maybe 400). With the 7D, sometimes ISO 400 could be problematic because of it's vertical banding issue. With the 5D III, I don't suspect it will be a problem, however for these birds, I'll probably be at 1200mm f/8, so I'd probably be using ISO 1600 instead. 

Anyway, when it comes to bird and wildlife photography, dynamic range is just not an issue. It could be an issue, it probably was a few years back when I was a noob and didn't know what I was doing...but with the skill I have (and I'm not the most skilled photographer by any means, I am sure I still have many years left of learning just with bird photography, let alone wildlife, landscaps, and all the other things I like to photograph), dynamic range with birds, deer, coyotes, etc. is just never a problem. I control the lighting, as ironic as that may be to say when talking about the sun. I control it because I control the angles involved between subject, photographer, and light source. Get the right angle, and you can reduce dynamic range in the scene to practically nothing (although then your often left with a bland, uninteresting image because it has no contour, so I rarely aim for minimal DR, but I do aim to minimize it so it fits within the capabilities of my hardware), then shooting at high ISO is not a problem.


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## neuroanatomist (Aug 10, 2014)

jrista said:


> Regarding birds and DR...to be honest, I have not found that dynamic range is the issue when photographing birds.
> 
> ...I rarely aim for minimal DR, but I do aim to minimize it so it fits within the capabilities of my hardware), then shooting at high ISO is not a problem.



I haven't found DR to be limiting, either. Noise at high ISO, on the other hand, I have found limiting with the 7D. Overall since getting the 1D X, I am using higher ISOs for birds, and still getting less noise. I strove to keep the 7D under ISO 1600...with the 1D X, that bar has gone up to ISO 6400. One consequence for example is that now, artistic wing blur is a choice rather than a concession.


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## roguewave (Aug 10, 2014)

jrista said:


> Your talking about on a per-pixel basis. On a per-pixel basis, that is true. However I'm talking about on a whole-image basis, or as it's called, on a "normalized" basis. When you compare images as a whole at the same size, assuming the same absolute area of sensor was used, then there won't be any difference in noise regardless of pixel size. There will, however, be a difference in detail.
> 
> This all assumes same pixel generation. The 5D III does have an advantage in upsampling due to it's newer pixel generation. It has higher quantum efficiency and overall a better pixel architecture, than the 7D pixels. That means less noise per pixel. I actually wish I had a 70D. That would make for a better comparison, as then both cameras would use sensors of similar generation, instead of being separated by over three years of technology. That's unlikely to happen unless I meet someone with a 70D who will let me borrow it for a night, though...as I have no intention of buying a 70D.



Jrista, thank you for the comparison! I found it very interesting.

I believe your experiment also shows that the current Canon FF sensors do not outresolve good lenses - contrary to some claims I've seen on this forum, essentially saying that lenses are the limiting factor and higher resolution FF sensors are pointless.


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## jrista (Aug 10, 2014)

roguewave said:


> jrista said:
> 
> 
> > Your talking about on a per-pixel basis. On a per-pixel basis, that is true. However I'm talking about on a whole-image basis, or as it's called, on a "normalized" basis. When you compare images as a whole at the same size, assuming the same absolute area of sensor was used, then there won't be any difference in noise regardless of pixel size. There will, however, be a difference in detail.
> ...



Personally, I believe the idea of a lens "outresolving" a sensor, or a sensor "outresolving" a lens, is a misleading concept. Output resolution is the result of a convolution of multiple factors that affect the real image being resolved. Sensor and lens work together to produce the resolution of the image you see in a RAW file on a computer screen...one isn't outrsolving the other. I've gone over that topic many times, so I won't go into detail again here, but ultimately, the resolution of the image created by both the lens and sensor working together in concert is closely approximated by the formula:


```
(1/SQRT(lensSpot^2 + sensorPixelPitch^2))/2
```

You can run that formula for any sensor and any lens at any aperture, and determine the theoretical maximum resolution that the two together can resolve.


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## serendipidy (Aug 10, 2014)

Jrista,
Great images and informative discussion. I have learned a lot. Very confusing to noobs. I remember someone on CR frequently talking about better resolution being related to " number of pixels on target." So with reach limited subjects, you need either higher focal length lens or more (ie smaller) pixels per area on the sensor, to get better detail resolution. Did I say that correctly?


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## LetTheRightLensIn (Aug 10, 2014)

neuroanatomist said:


> jrista said:
> 
> 
> > ...certainly not as stark a difference as my first example. Maybe that one is invalid. This example, however, does show that the 7D is still picking up more subtle details and nuances of color. The differences are not stark, but they do exist.
> ...



Noticeably more detail on a Hairy Woodpecker at something ISO1600-2500. Noticeably more detail on a dollar bill at ISO6400 (this one was of course a high contrast subject in a well lit portion of the frame, so for a camera like the 5D3/1DX (although NOT 5D2) at some point if the subject is enough of a combination of low contrast, dark coloration, in a dark part of the frame the reach advantage might go away and the overall look might eventually end up nicer with the 5D3/1DX).


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## LetTheRightLensIn (Aug 10, 2014)

roguewave said:


> I believe your experiment also shows that the current Canon FF sensors do not outresolve good lenses - contrary to some claims I've seen on this forum, essentially saying that lenses are the limiting factor and higher resolution FF sensors are pointless.



That really wouldn't even make sense if you think about it properly. Sure FF cams have more MP, but the MP are spread over such a much larger area that they have lower density than current APS-C cameras. It should be the aps-c cameras where such a limitation is to be first noticed.

It's not some sudden limit kinda thing though. You can see that even the crummy lenses on say photozone.de, that lag behind on some old camera they test with low density, nonetheless often give a final result on a high mp camera that is more more lines per inch. At some point though with a poor enough lens and high enough density the gains will fade to nothing of any significance though (and quite a few lenses already hit that point at FF extreme edges and corners even at current densities, many if talking about wide open)


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## jrista (Aug 10, 2014)

serendipidy said:


> Jrista,
> Great images and informative discussion. I have learned a lot. Very confusing to noobs. I remember someone on CR frequently talking about better resolution being related to " number of pixels on target." So with reach limited subjects, you need either higher focal length lens or more (ie smaller) pixels per area on the sensor, to get better detail resolution. Did I say that correctly?



Yeah, that's correct. BTW, it's me who has always said "pixels on target".  I read that a long time ago on BPN forums, from Roger Clark I think, and started experimenting with it. I think it's the best way to describe the problem...because it scales. It doesn't matter how big the pixels are, or how big the sensor is...more pixels on target, the better the IQ. If you are only filling 10% of the frame, try to fill 50%. It doesn't matter if the frame is APS-C, FF, or something else...it's all relative.


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## scyrene (Aug 10, 2014)

jrista said:


> So, I thought I'd throw in a bit of a "reference image". One way to image more detail, even when seeing is bad, is to take a lot of frames at high shutter speeds, and integrate the best 10-20%. It's called Lucky Imaging (lucky, in that in some of the frames you image, you'll be "lucky" enough to have very good to perfect seeing, where the turbulence clears and everything resolves at high resolution. The exposure duration can range anywhere from a few hundred milliseconds to microseconds. In my case, I kept my exposure settings, so my exposure duration was 10ms.
> 
> I took a couple of videos of the shadowed limb of the moon at 1000 frames at 5x zoom, and integrated the best 10% (100 frames) with AutoStakkert! 2. I used the 3x Drizzle option, which is actually a superresolution algorithm, then downsampled to 50% (1.5x original resolution), so the final image is actually showing detail beyond the diffraction and aberration limits of the optics. This is the result:
> 
> ...



I wish I had the processing skill and knowledge you do! It's impressive how much detail you can pull out at these focal lengths. I went the other way, increasing FL until I got results I was content with, although eventually the extra glass (stacked teleconverters) degrades image quality and it seems to even out. Still, I feel more data can be pulled out of my setup, if only I knew how.

Good stuff, as ever.


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## 100 (Aug 10, 2014)

jrista said:


> 100 said:
> 
> 
> > Nice comparison. Thanks for posting.
> ...



The DLA of the 7D is f/6.9 so shooting at f/8 is theoretically not the optimal f-number and iso 160 seems to be the cleanest iso for the 7D. 
My experience with the 18mp crop sensor versus the 22mp FF sensor is that they need different processing in ACR (noise reduction, sharpening, etc.) for optimal results. 

Another thing about ISO. A FF sensor is 2.6 times bigger, so it can gather 2.6 times the amount of light, but if your subject doesn’t fill the sensor area and everything around it is basically black with the same lens and the same settings the total amount of light hitting the sensor will be the same for both sensors, so there is no ISO advantage due to sensor size. The 5DmkIII gets more light per pixel due to bigger pixels but has less pixels on the subject. However these camera’s don’t have the same generation pixels and in camera processing so the 5DmkIII will perform better as far as noise in concerned. The 7D will perform better on resolution/detail and by the looks of it you gain more detail with smaller pixels than you lose with the higher amount of noise reduction needed. At least at low ISO setting.


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## weixing (Aug 10, 2014)

Hi,
Today, I do a compare shots on FF vs APS-C on a real bird under real life condition... only manage to try out ISO 1600 and ISO 3200 as start to rain very heavily after this. I just open them using lightroom 4, took a screenshot, paste on paint and saved as jpeg. 
*Test Condition*
*Camera:* Canon 6D (left) vs Canon 60D (right)
*Lens:* Tamron 150-600mm @ F8
*Subject:* Stork-billed Kingfisher at around 18m (this is the only real bird that I can find that will stay at the same place for extended period of time with minimum movement).
*Weather:* Cloudy

Below are the shots:

*6D vs 60D ISO 1600 (1:1)*





*6D vs 60D ISO 1600 (2:1)*





*6D vs 60D ISO 1600 (1:0.5)*





*6D vs 60D ISO 3200 (1:1)*





*6D vs 60D ISO 3200 (2:1)*





*6D vs 60D ISO 3200 (1:0.5)*





After looking at the compare shots, my initial conclusion is that the 60D sensor doesn't seem to have a significant details advantage (if any) under real life condition (at least this seem to be true when using the Tamron 150-600mm lens) over the 6D and the 6D (up to ISO 3200) doesn't seem to have a real noise advantage if the 60D image was scale down.

Have a nice day.

PS: The CanonRumors website seem to scale down the screenshot image (actual size is 1920 x 1080) to fit the website frame... to view at actual size, need to click on the image and using the scroll bar below the post to scroll through the image... or is there a setting to show the image actual size??


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## Northstar (Aug 10, 2014)

All this makes me salivate for a 7D2, and also a large MP FF that I can get more reach with...


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## Lightmaster (Aug 10, 2014)

thx for the tests.


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## docsmith (Aug 10, 2014)

Another 7D to 5DIII convert here. I don't dispute that the 7D could out resolve the 5DIII in certain circumstances. Your second comparison with the moon is more inline with my tests than the first. But as I was evaluating the two bodies, for me, it became more than just about resolving power. The color, transition from the highlights and blacks, noise, etc, were what stood out to me as the primary differences.

The 7D is an amazing camera. I shot with it for years. I would not hesitate to recommend it.

And I make this post knowing this thread is titled "The Reach War," but I was a little surprised that no one else had yet brought up that the differences between the 5DIII and 7D (or 70D) is about more than reach and noise.

That said, I will watch reviews and comments on the 7DII. It would be nice to have the extra reach if everything else is up to speed. The 7DII with a 100-400L would be easier to travel with and cheaper than a 600 II. But, I haven't shot my 7D since the early tests with the 5DIII. Even for birds. I prefer the shots taken from the 5DIII. Sometimes I miss the reach, but, overall, I prefer the images.


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## MichaelHodges (Aug 10, 2014)

LetTheRightLensIn said:


> You won't?? Even if you use say a 7D and a 5D2 and the 7D sensor is more efficient at collecting and converting photons per area of surface than the 5D2?? With the 7D you can chose to get either: more detail (unless conditions are super bad) and more noise OR slightly better detail with less de-bayer and other artifacts and slightly better noise (if you view or convert to same scale as the 5D2).



Unfortunately it doesn't work that way in crepuscular conditions. You can have all the "pixels on target" you want, but if the sensor can't handle the low lighting (7D), you're not going to get the shot. And by "shot", I mean something you can print at 16x20.

When shooting in RAW during the November white-tail rut in Montana, my 7D becomes almost useless. The sun comes up at 8:30, and light gets shaky around 4:30 thanks to consistent, thick cloud cover. It's often snowing or raining. Once I start hitting 1600 ISO on the 7D, it's time to put it away. Out comes the full frame, where I can get usable images at ISO 12,800. Not to mention that my other cameras do a much better job of focusing on low contrast targets (brown deer with a brown background) than the 7D.

In these cases, noise is the bottleneck.


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## MichaelHodges (Aug 10, 2014)

jrista said:


> Regarding birds and DR...to be honest, I have not found that dynamic range is the issue when photographing birds.



So two golden eagles swooping in to take out a bald eagle at your back, silhouetted in the sun doesn't present a DR issue? What about bighorn rams fighting each other in uneven forest light? People wait all year for those moments, heck, they wait years. A second later, it could be gone. 

Dynamic range is the single biggest issue with *wild*life photography, IMHO. That's why the shadow recovery in the Sony sensors is so appealing.




> Anyway, when it comes to bird and wildlife photography, dynamic range is just not an issue.




I completely disagree. It's *the* issue. Are you going to sneak around a grizzly bear in the bushes to get the right angle? (that's a great way to get yourself killed). Or how about tramping in the willows on a mountain lake to get just the right light on a bull moose? (another good way to get killed). What about when a squirrel decides to watch sunrise over Glacier Point in Yosemite? Are you going to command the sun to rise from the west so you can get the good light? If you are shooting tame birds or zoo animals, maybe it's not much of an issue. But for actual wildlife? Top of the list.

The only one with the control in wildlife photography is the animal. They do what they want, when they want, and under the lighting conditions they see fit. It's your job to take the punches and get to the 12th round.


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## AlanF (Aug 10, 2014)

MichaelHodges said:


> jrista said:
> 
> 
> > Regarding birds and DR...to be honest, I have not found that dynamic range is the issue when photographing birds.
> ...



+1 My biggest mistakes are when my camera is set for point exposure for birds against a normal background and one flies by against the sky and I don't have time to dial in +2 ev to compensate or vice versa. Two more stops of DR would solve those problems.


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## AlanF (Aug 10, 2014)

jrista said:


> serendipidy said:
> 
> 
> > Jrista,
> ...



It is not true as a general statement that the more pixels on target, the better. There have to be optimum sizes of pixels and optimal numbers on target, as shown by the following arguments. The signal to noise of a pixel increases with its area: the bigger the pixel, the greater the number of photons flowing through it and the greater the current generated, and the statistical variation in both becomes less important. The dynamic range is also greater for large pixels than can accommodate a large number of electrons. A low megapixel sensor should have very good signal to noise and DR, but poor resolution. Now, see what happens as we progress to the other extreme. As, we decrease the size of the pixel, the resolution increases but the statistical noise starts to increase as the number of photons hitting each pixel decreases per unit time. The electrical noise also increases until the inherent noise in the circuit becomes greater than that due to the fluctuation in number of electrons generated by the photons. We all experience this as the noise caused by increasing the iso setting. The dynamic range also decreases. Eventually, the pixel becomes so small that it loses all of its dynamic range because the well is so shallow it can hold only a few electrons.

So, too large a pixel gives too little resolution, too small a pixel gives too much noise and too small dynamic range. You could have a 20 billion too small useless pixels on target where 20 million would be the optimal number. Because of the above reasoning, astrophotographers and astronomers match pixel size to their telescopes. For photographers, the optimal size for current sensors pixels is around the range of crop to FF.


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## AlanF (Aug 10, 2014)

jrista said:


> Personally, I believe the idea of a lens "outresolving" a sensor, or a sensor "outresolving" a lens, is a misleading concept. Output resolution is the result of a convolution of multiple factors that affect the real image being resolved. Sensor and lens work together to produce the resolution of the image you see in a RAW file on a computer screen...one isn't outrsolving the other. I've gone over that topic many times, so I won't go into detail again here, but ultimately, the resolution of the image created by both the lens and sensor working together in concert is closely approximated by the formula:



It is not a misleading concept, just one that has to be used carefully. There are many processes in physics and chemistry where the end result is related to the all the components usually summed as reciprocals; e.g. resistors in parallel in an electric circuit; the overall resolution of an optical system, etc. Where those components all make similar contributions, none of them dominate and all are taking into the reckoning. E.g, a 1 ohm resistor in parallel with a 1 ohm has an overall resistance if 0.5 ohms. However, if dominates the system then the others are unimportant - the overall resistance of a 1 ohm resistor in parallel with a 100 ohm, is little different from a 1 ohm parallel with a million ohm, all very close to 1 ohm. If a lens at a particular aperture produces a point source that gives an image much smaller than a pixel, then increasing the number of pixels could be useful to increase resolution as the lens is outresolving the sensor. If the lens projects a point source to a size that is much larger than the size of a pixel, the sensor is outresolving the lens and it is a waste of time increasing the number of pixels. When the point size is similar, the situation is indeed more complicated as neither dominates.


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## neuroanatomist (Aug 10, 2014)

MichaelHodges said:


> Dynamic range is the single biggest issue with *wild*life photography, IMHO.



Ok, but...



MichaelHodges said:


> I can get usable images at ISO 12,800.



So <10 stops is sufficient? 

I don't think anyone is saying DR is unimportant, just that some of us don't routinely encounter high DR scenes in bird/wildlife photography. You frequently state you commonly shoot in crepuscular light, I'm not sure if you mean that specifically or actually mean 'late in the day' but use 'crepuscular' because it's a nice word. Crepuscular is twilight, which occurs after the sun drops below the horizon. Since there usually aren't many sources of artificial light in the wild, after the sun goes down there's not a whole lot of scene DR.


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## Lee Jay (Aug 10, 2014)

AlanF said:


> It is not true as a general statement that the more pixels on target, the better. There have to be optimum sizes of pixels and optimal numbers on target, as shown by the following arguments. The signal to noise of a pixel increases with its area:



But the signal to noise ratio of a given sensor area does not increase with increasing pixel size.


> The dynamic range is also greater for large pixels than can accommodate a large number of electrons.



This is also untrue or the G15 wouldn't have more base ISO DR than the 1Dx despite having pixels with 1/14th as much area..

http://www.sensorgen.info/CanonPowershot_G15.html
http://www.sensorgen.info/CanonEOS-1D_X.html


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## pdirestajr (Aug 10, 2014)

The difference is "Neg-li-gi-ble."


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## MichaelHodges (Aug 10, 2014)

neuroanatomist said:


> I don't think anyone is saying DR is unimportant, just that some of us don't routinely encounter high DR scenes in bird/wildlife photography. You frequently state you commonly shoot in crepuscular light, I'm not sure if you mean that specifically or actually mean 'late in the day' but use 'crepuscular' because it's a nice word. Crepuscular is twilight, which occurs after the sun drops below the horizon. Since there usually aren't many sources of artificial light in the wild, after the sun goes down there's not a whole lot of scene DR.



In this context its usage describes animal behavior like deer, bear, moose and so forth. These animals (especially what some would consider 'trophies') are more active during crepuscular periods. For those who shoot big mammals, crepuscular periods are "go time". Anything can and does happen. This is where the APS-C gets switched off and the FF comes out. You'll get better shutter speeds and far less noise overall. 

I think there are valid points to using APS-C for small birds in daylight or prime lighting conditions. But for me, the true test of a camera is how it does in unfavorable conditions. The FF will perform admirably in these lowlight periods and capture moments in relatively clean detail.


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## RustyTheGeek (Aug 10, 2014)

Wow! I just want to say that my inner engineer geek and photographer geek are really having a blast reading this thread! I know enough to follow the concepts but I also know when my understanding isn't solid yet. When I have more time I'm going to read it through at least once or twice more! This thread is why I stick with the CR forum! The in-depth information I'm seeing and back & forth discussion are riveting.

Thanks so much for putting so much effort and time into this (and many other threads). I'm sure some are reading this and saying, "Who Cares?" but not me. I'm seriously geeking out here. 

My comments on the thread so far are...

- While I understand what *neuro* and *jrista* are saying about DR, I agree with *MichaelHodges* in that DR carries more significance. At least for me it does for some of the same reasons he states. I bristled a bit when I read jrista's DR opinions. Of course, I'm not shooting wildlife as often as I'm shooting boy life (scouts running around, etc) but the same factors apply, except I probably won't be killed!

- I've read things in the past about lens resolution vs. sensor resolution and while some of the discussions seemed to have a lot of evidence and facts to back up the theory, my gut has never believed it. Good glass is good glass and if it was good enough to produce a beautiful image on film in the '90's, it should still be good enough to produce a beautiful image on a sensor in 2010. The light, the glass and the sensor don't know when the lens was made, they just do their thing. If the glass is clean, aligned correctly and focused properly, the image should be sharp. If a newer technology lens uses better glass, coatings and IS so there is less light corruption then the picture should improve from those upgrades but not because the resolution of the sensor "matches" the resolution of the lens. This idea has never sat well with me.

- *jrista*, the techniques you are using on the the moon to get sharper images, etc are impressive. I'm really enjoying reading about some of the tricks and gear you are using to do it. I've always struggled with explaining to newbies why it is hard to photograph the moon with the gear they have when they can see the moon clearly with their eyes. I've explained a lot of the obvious stuff but you take it to whole other level! Wow!!


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## RustyTheGeek (Aug 10, 2014)

MichaelHodges said:


> I think there are valid points to using APS-C for small birds in daylight or prime lighting conditions. But for me, the true test of a camera is how it does in unfavorable conditions. The FF will perform admirably in these lowlight periods and capture moments in relatively clean detail.



I gots to say, this has been my experience as well which is why my FF bodies get 90% use while the 60D stays home now. But I would LOVE it if the 7D2 sensor is so good that this becomes a moot point. LOVE it.


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## Skulker (Aug 10, 2014)

jrista said:


> Skulker said:
> 
> 
> > jrista said:
> ...




That certainly shows much less of a difference. Have you corrected your original post? You shouldn't leave it with such an error.


Unfortunately as you aren't putting up the raw files, as so many have asked, we can't replicate your work and see if we get the same results. Unless I have missed the link to them.


On my monitor there is quite a color cast to the 5D3 images, but none on the 7D image.


Finally let me say although I have plenty of questions about your thoughts on the "crop factor" and how you have gone about proving your point. I have no issues with the quality of some of your photography and think the images you produce of the night sky are some of the best images seen on this site. ;D 


But you still haven't said so again "Whats with the 30 decimal places?" ;D ;D


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## AlanF (Aug 10, 2014)

Lee Jay said:


> AlanF said:
> 
> 
> > It is not true as a general statement that the more pixels on target, the better. There have to be optimum sizes of pixels and optimal numbers on target, as shown by the following arguments. The signal to noise of a pixel increases with its area:
> ...



There are factors other than pixel size that determine DR, which become the limiting factors for larger sensors - if size were the only factor then a Sony sensor would have the same DR as a Canon. However, it is basic physics that DR will eventually decrease with decreasing pixel size because of the number of electrons that can be accommodated in a well. 

The noise of individual pixels is important as well as the overall noise of a particular area of sensor. That is, the _overall_ signal to noise might be independent of the number of pixels, but the variation of signal within that area is what you actually see as noise. Suppose you take a photo of a pure blue background. With a very low pixel density, you will see a very flat blue image. With very high pixel density, you would see lots of colour variation when you pixel peep.


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## 58Special (Aug 10, 2014)

I use both the 5D mk III and the 7D. I like have both, it is like have two sets of lenses. That being said if i am close enough i will always go to the 5D.


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## scyrene (Aug 10, 2014)

MichaelHodges said:


> jrista said:
> 
> 
> > Regarding birds and DR...to be honest, I have not found that dynamic range is the issue when photographing birds.
> ...



I don't find this at all. Maybe it's the different lighting conditions here, maybe it's the animals I'm after (tends to be small perched birds). The most extreme DR cases are 1) a grey/white sky with bird on a twig, which is essentially a silhouette, and 2) a black and white bird in bright sunlight. In the former case, although it's rare these shots are ever very appealing (imho), the only way around it is to accept a blown out sky. At least you're not really losing anything (although the edges of the subject can look odd if you play around too much. In the latter case, I follow the rule of never blowing whites on the bird, so if that leads to the blacks being underexposed, so be it.

Dappled shade can be a challenge, but it's rare in my experience for the subject itself to be in both light and shade. Maybe because songbirds are smaller, I don't know. But I don't find the DR of my bird shots exceeds the sensor under most circumstances.


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## jrista (Aug 10, 2014)

scyrene said:


> jrista said:
> 
> 
> > So, I thought I'd throw in a bit of a "reference image". One way to image more detail, even when seeing is bad, is to take a lot of frames at high shutter speeds, and integrate the best 10-20%. It's called Lucky Imaging (lucky, in that in some of the frames you image, you'll be "lucky" enough to have very good to perfect seeing, where the turbulence clears and everything resolves at high resolution. The exposure duration can range anywhere from a few hundred milliseconds to microseconds. In my case, I kept my exposure settings, so my exposure duration was 10ms.
> ...



It's actually not difficult. AutoStakkert! 2 pretty much does all the work. You record a video, and since the moon in each frame is moving a little bit...due to atmospheric turbulence and due to it's transit across the sky (unless you have a tracking mount...then it will move a little bit due to periodic error of the mount), the position of the moon and its features change just a little frame to frame. That allows advanced algorithms to be used to figure out what the "right" value is for each pixel, and even enhance resolution by using superresolution algorithms like drizzle. All you really have to do is record the video, and perform three steps in AutoStakkert! (load image, analyze, stack).


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## jrista (Aug 10, 2014)

weixing said:


> Hi,
> Today, I do a compare shots on FF vs APS-C on a real bird under real life condition... only manage to try out ISO 1600 and ISO 3200 as start to rain very heavily after this. I just open them using lightroom 4, took a screenshot, paste on paint and saved as jpeg.
> *Test Condition*
> *Camera:* Canon 6D (left) vs Canon 60D (right)
> ...



Very interesting results. Congrats on finding a bird that would sit still the entire time you took the shots.  That's definitely the kind of bird you need. 

To really truly compare, you would need to overlay the two images on top of each other, and upscale the 6D images so the bird was the same size, then overlay them directly on top of each other (Photoshop's difference layer blending mode makes the positioning very easy). Then you can swap back and forth, and really see the difference. It's pretty much impossible to objectively determine any real differences when looking at the images side-by-side...it becomes almost a pure subjective judgement. 

The only other thought I have is the lens used. The 150-600 is a good lens for it's price class, but I can tell it does not resolve the same kind of detail as the EF 600 f/4 II. I am able to resolve fine feather and fur detail even at very high ISO, something I don't see in your images. It doesn't necessarily invalidate the test, however it does throw in a major factor that affects results. The moon is a bit of a different kind of subject than a bird, given that it is primarily seeing limited rather than diffraction limited, so using 1200mm f/8 does not limit resolution the way it would with a terrestrial subject. If I were to do a bird test...I would probably use the 600 at f/4.5, which seems to be the absolute sweet spot of my lens.


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## scyrene (Aug 10, 2014)

jrista said:


> scyrene said:
> 
> 
> > jrista said:
> ...



Is that software Windows-only? I did a bit of searching, and couldn't find system requirements anywhere. For some reason, most of this sort of software doesn't run on Macs, so I had to use the only stacker I could find that did, called 'Keith's Image Stacker'. It's pretty good but I have no understanding of how different modes produce different results. I guess I should read up on it more.

As for video - this is a question I've had for a while. Even HD video is only 2MP. No matter how much resolution you're gaining through stacking, surely you're losing 90% (of the 5DIII's potential) versus stills? Any thoughts? When I stacked my moon (I've included a crop of a much reduced-size below) I had to shoot lots of stills manually and use those instead. You're clearly doing something better though, as you seem to be pulling out a similar level of detail even though I was at a much higher focal length (5600mm).


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## jrista (Aug 10, 2014)

MichaelHodges said:


> LetTheRightLensIn said:
> 
> 
> > You won't?? Even if you use say a 7D and a 5D2 and the 7D sensor is more efficient at collecting and converting photons per area of surface than the 5D2?? With the 7D you can chose to get either: more detail (unless conditions are super bad) and more noise OR slightly better detail with less de-bayer and other artifacts and slightly better noise (if you view or convert to same scale as the 5D2).
> ...





MichaelHodges said:


> jrista said:
> 
> 
> > Regarding birds and DR...to be honest, I have not found that dynamic range is the issue when photographing birds.
> ...



I decided to combine your two posts, because I think the context of the two matter here. First, you talk about crepuscular conditions. You have brought that up a couple times in the past as well, and it is a valid point. However I think it is a point at odds with the points you make in the second post. 

In crepuscular light, the low light around sunrise and sunset, you are NOT going to be using ISO 100 or 200. As you say, your going to be up at ISO 12800. You need the high ISO so you can maintain a high shutter rate, so you can freeze enough motion to get an acceptable image. There are times during the day when you can capture wildlife out and about, but the best times are indeed during the crepuscular hours of the day. 

Just for reference, here are the dynamic range values for four key cameras at ISO 12800:

D810: 7.3
D800: 7.3
5D III: 7.8
1D X: 8.8

As far as dynamic range for wildlife and bird photography during "activity hours" goes, there is no question the 1D X wins hands down. It's got a 1.5 stop advantage over the D800/D810, the supposed dynamic range kings. At ISO 6400, we have:

D810: 8.3
D800: 8.3
5D III: 8.5
1D X: 9.7

At ISO 3200 we have:

D810: 9.2
D800: 9.2
5D III: 9.5
1D X: 10.5.

At ISO 1600 we have:

D810: 9.8
D800: 9.8
5D III: 10.1
1D X: 10.8

And finally, at ISO 800 we have:

D810: 10.8
D800: 11.2
5D III: 10.5
1D X: 11.1

It is not until we reach ISO 800 that the D800 series cameras start to close the cap and overtake the high ISO advantage of Canon cameras high ISO DR. It is certainly possible to shoot at ISO 800, and ISO 400, in the hour leading up to sunset...I have shot at those settings myself. However shadows are long during that hours, and it is more common that I am shooting at a higher ISO. It is only the hour or two around the two-hour period of midday that I ever find myself shooting at ISO 100 or 200...and then, it is rarely with fast moving subjects like a Golden Eagle flying directly at me to fight with another bird behind me. I'd again be at a higher ISO to guarantee I have the shutter speed I need to capture that action with just the right amount of motion blur in the wing tips, but otherwise freezing the motion of the bird itself. 

Regarding pixels on subject...I'm confused why you would say that doesn't matter. If you increase the size of your subject relative to the size of your pixels, that means that the frequency of the noise becomes higher and higher relative to the subject. It really doesn't matter if you are at a higher ISO or not...the frequency of noise is still based on the pixel pitch. If I take two shots of a deer, at ISO 12800, and in one the deer fills 33% of the frame and in the other the deer fills 66% of the frame. Which image is going to have better IQ? The one where the deer fills 33%? No, of course not. The image where the deer is larger in the frame...the image where there are "more pixels on the deer", is going to have the better IQ. The deer is much larger, so all that ISO 12800 noise is going to be less intrusive, as in terms of relative frequency, the noise is much smaller. 

Whether the 7D is useful or useless depends on exactly that. Pixels on subject. I've been able to make very good use of my 7D under very difficult lighting conditions by taking the time to get the subject framed right, and getting it frames large enough. Even at very high ISO:






This night heron was shot at ISO 3200, but underexposed by about a stop (I'd had my 7D configured to limit which ISO settings would be automatically selected at the time, and I was shooting Auto ISO). The shutter speed was 1/6th second. This was with the 600mm f/4 L II, well after sunset...blue hour was on, and there were dark clouds blocking a lot of the remaining post-sunset light. The only reason I was able to make anything of the shot and still have this much detail was because I managed to get enough pixels on the bird that it could withstand the editing. 

So, first off, I do not believe that the argument that the enhanced DR of the Sony sensors is useful when it comes to wildlife or bird photography. On the contrary, given the measurements, it seems like the Canon cameras do indeed have the DR edge, especially the 1D X, and especially at the higher ISO settings that are critical during the hours wildlife is most active. 

To address a couple points more specifically. The silhouette scene...a bird silhouetted is a bird silhouetted. Either it is a dark subject against a very bright background, or it's not. If we are talking about something where a bird is silhouetted against bright sunlit water, even a D800 is going to struggle with that....assuming you even had the option of shooting at ISO 100. The likelihood is that your using a much higher ISO (pretty much GUARANTEED in the "two golden eagles flying in with the sun at their backs" case) in which case there is no advantage to using a D800 or having more DR. In that situation, you do something like this:









You make the images REAL silhouettes...pure shadow superimposed over a brighter background.

When it comes to other animals, like bull moose or elk, bears, or the squirrel that wants to watch sunset. Well, starting with the squirrel...I would certainly do what I could to get on the western side of it. I mean, we are talking about good lighting here, lighting that does your subject justice. Aside from silhouetting your subject, shooting from the back side directly into sunlight is not the most flattering light for a wildlife subject. It might make for one interesting photo one time, but in general, I look for the scenes and angles where my subjects are better lit. The sun does not necessarily need to be directly at your back. Actually, having the sun DIRECTLY at your back is not good either, as it flattens your subject. There needs to be a certain angle, and sometimes you can suffer a little bit of loss on the DR front (i.e. end up with slightly too much DR in the scene than you can really handle) in order to get a shot that might otherwise not be possible. 

Regarding moose, elk, deer, etc. I absolutely do what I can to get a better angle on them. But you pick your battles, for sure. Deer, elk, etc. are quite docile during the earlier parts of the year. It is only really during the rut and their mating season that they take on a hostile stance. That is where having a big long lens, and some TC's and, maybe even, a cropped sensor, become really handy. They give you a much more comfortable working distance when photographing rutting wildlife. 






Here is an example where I did what I could to get the right angle of light, during crepuscular hours. Light still coming from more of an angle than I wanted, the elk's body is decently lit but the beard is more shadowed than I wanted, but shot still came out quite nicely. In this particular situation, for the given exposure, a D800 would not have offered me much in the way of advantages over the 7D...I was reach limited, I was at very high ISO. The D800 might have had slightly more DR, but less resolution, and similar per-pixel noise...but a considerably slower frame rate.

So, at least in my experience, given that I rarely have the opportunity to shoot wildlife of any kind at ISO 100, and were not talking about zoo animals here, but real WILD life...I do not believe DR is a critical issue with wildlife photography. You simply don't have 12 or 14 stops at ISO settings from 400 and up. At the really high ISO settings we use during crepuscular hours, ISO 3200, 6400, even 12800, we might not even have EIGHT stops of DR! I also do not believe it is impossible to situate yourself, the photographer, at the right angle to your subject such that it is properly lit, therefor minimizing or eliminating DR issues in the first place. Even in the cases where DR might become an issue, such as backlit subjects...if you look at the photography of well-respected wildlife pros, like Andy Rouse...he doesn't try to lift the shadows of a shaded backlit subject like an African wildcat by many stops. He leaves them shaded, he leaves them contrasty. Sometimes it just isn't about dynamic range...sometimes, dynamic range really, truly, doesn't matter...


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## jrista (Aug 10, 2014)

AlanF said:


> +1 My biggest mistakes are when my camera is set for point exposure for birds against a normal background and one flies by against the sky and I don't have time to dial in +2 ev to compensate or vice versa. Two more stops of DR would solve those problems.



This is a case where you want more DR to eliminate the need for the photographer to make the necessary exposure change. If you encounter this situation a lot, I highly recommend reading Art Morris' blog, and maybe buy his book "The Art of Bird Photography". He has an amazing technique for setting exposure quickly and accurately, such that making the necessary change quickly to handle this situation properly would not be a major issue. 

Personally, I wouldn't consider this a situation where more DR is *necessary*. It might be a situation where more DR solves a problem presented by a lack of certain skills...but it is not actually a situation where more DR is really necessary.


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## weixing (Aug 10, 2014)

Hi,


jrista said:


> weixing said:
> 
> 
> > Hi,
> ...


 I had no doubt that EF600mm F4 II with it's 150mm front element will resolve more details compare to my 95mm front element, but I'm $$ limited... ha ha ha ;D 

Anyway, the sky is cloudy and the bird is under the shade... so I think the details are a bit more difficult to resolve under this flat lighting condition.

Have a nice day.


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## jrista (Aug 10, 2014)

AlanF said:


> jrista said:
> 
> 
> > serendipidy said:
> ...



True. However that does not falsify my claims about pixels on target. We don't look at pixels. We look at images. Noise is relative to area. If you take 6.25µm pixels and 4.3µm pixels, you can fit 2.1 of the smaller pixels into every one of the larger pixels. Assuming the same technology (which is not actually the case with the 5D III and 7D...but humor me here), those 2.1 smaller pixels have the same amount of signal, and therefor the same amount of noise, as the single larger pixel. Noise is relative to area. If you increase the area of the sensor which your subject occupies, you reduce noise as a RELATIVE FACTOR. 




AlanF said:


> The dynamic range is also greater for large pixels than can accommodate a large number of electrons. A low megapixel sensor should have very good signal to noise and DR, but poor resolution. Now, see what happens as we progress to the other extreme. As, we decrease the size of the pixel, the resolution increases but the statistical noise starts to increase as the number of photons hitting each pixel decreases per unit time.



Per-pixel noise is an absolute factor. You are absolutely right that larger pixels have less noise and higher dynamic range. However ultimately, to maximize IQ, you don't want to achieve some arbitrary balance between pixel size and pixel count. You simply want to maximize the number of pixels on subject, regardless of their size. Because it really isn't about the pixels...it's about the area of the sensor your subject occupies. 

In a reach-limited situation, the absolute area of the sensor occupied by your subject is fixed...it doesn't matter how large the sensor is. You will be gathering the same amount of light in total for your subject regardless of what sensor your using, or how big it's pixels are. Therefor, the only other critical factor to IQ is detail...smaller pixels are better, in that case, all else being equal. 



AlanF said:


> The electrical noise also increases until the inherent noise in the circuit becomes greater than that due to the fluctuation in number of electrons generated by the photons. We all experience this as the noise caused by increasing the iso setting. The dynamic range also decreases. Eventually, the pixel becomes so small that it loses all of its dynamic range because the well is so shallow it can hold only a few electrons.



Actually, electronic noise within the pixels themselves, ignoring all other sources of read noise (which tend to be downstream from the pixels) is due to dark current. Dark current noise is relative to pixel area and temperature...and dark current noise DROPS as pixel size drops. The amount of dark current that can flow through a photodiode is relative to it's area, just like the charge capacity of a photodiode is relative to it's area. So, technically speaking, electronic noise does not increase as pixel size decreases. Again, dark current noise is relative to the unit area...pixel size, ultimately, does not matter. 

When it comes to read noise overall, that actually has far less to do with pixel size, and far more to do with the downstream pixel processing logic, how it's implemented, the frequency at which those circuits operate, etc. Most read noise comes from the ADC unit, especially when they are high frequency. I've seen read noise in CCD cameras that use Kodak KAF sensors change from one iteration to the next. A camera using a KAF-8000 series had as much as 40e- read noise a number of years ago. The same cameras today have ~7e- read noise. They are identical sensors...the only real difference is read noise. That's because read noise isn't a trait inherent to the sensor...it's related to all the logic that reads the sensor out and converts the analog signal to a digital signal. Canon could greatly reduce their read noise, without changing their sensor technology at all...because the majority of their noise comes from circuitry off-die in the DIGIC chips.



AlanF said:


> So, too large a pixel gives too little resolution, too small a pixel gives too much noise and too small dynamic range. You could have a 20 billion too small useless pixels on target where 20 million would be the optimal number. Because of the above reasoning, astrophotographers and astronomers match pixel size to their telescopes. For photographers, the optimal size for current sensors pixels is around the range of crop to FF.



Your ignoring the fact that you can always downsample an image made with a higher resolution sensor to the same smaller dimensions as an image made with bigger pixels. The 7D and 5D III are the cameras I used because they are the cameras I have. I often use the term "all else being equal" in my posts, because it's a critical factor. The 7D and 5D III are NOT "all else being equal". They are a generation apart. The 7D pixels are technologically inferior to the 5D III pixels. 

So, ASSUMING ALL ELSE BEING EQUAL, there is absolutely no reason to pick larger pixels over smaller pixels, assuming your going to be framing your subject the same with identical sensor sizes. If your photographing a baboon's face, and you frame it so that face fills the frame with a nice amount of negative space. If you have a 10mp and 40mp camera, You should ALWAYS pick the sensor with smaller pixels. You can always downsample the 40mp image by a factor of two, and you'll have the same amount of noise as the 10mp camera. Noise is relative to unit area. It doesn't matter if that unit area is one pixel in a 10mp camera, or four pixels in a 40mp camera...it's still the same unit area. Average those four smaller pixels together, and you reduce noise by a factor of two. Which is exactly the same thing as binning for pixels during readout, which is also exactly the same thing as simply using a bigger pixel.

The caveat, here, is that with a 40mp sensor, you have the option of resolving more detail. You plain and simply don't have that option with the 10mp sensor. More pixels just delineates detail...and noise...more finely. Finer noise has a lower perceptual impact on our visual observation. If the baboon face is framed the same, then your gathering the same amount of light from that baboon's face regardless of pixel size. Photon shot noise (the most significant source of noise in our photos) is intrinsic to the photonic wavefront entering the lens and reaching the sensor. Smaller pixels simply delineate that noise more finely.


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## jrista (Aug 10, 2014)

AlanF said:


> jrista said:
> 
> 
> > Personally, I believe the idea of a lens "outresolving" a sensor, or a sensor "outresolving" a lens, is a misleading concept. Output resolution is the result of a convolution of multiple factors that affect the real image being resolved. Sensor and lens work together to produce the resolution of the image you see in a RAW file on a computer screen...one isn't outrsolving the other. I've gone over that topic many times, so I won't go into detail again here, but ultimately, the resolution of the image created by both the lens and sensor working together in concert is closely approximated by the formula:
> ...



Your basically talking about asymptotic relationships in systems that resolve. You are indeed correct, just like resistors in a circuit, output resolution is bound by the lowest common denominator. If the sensor is the limiting factor, which would be the case if the lens was resolving a spot smaller than a pixel, then yes...you would want to increase sensor resolution to experience more significant gains. 

I think my opinion diverges from yours when talking about if the lens is resolving a larger spot than the lens. That doesn't suddenly mean increasing sensor resolution is useless. I wouldn't say there is a hard wall there. Once the spot of light resolved by a lens starts growing larger than a pixel, that is the point at which you first start experiencing diminishing returns. There is still value in increasing the resolution of the sensor, however. You begin to oversample...however, in the grand scheme of things, oversampling is actually good. If we had sensors that were consistently capable of oversampling the diffraction spot of a diffraction limited lens by about 3x, then we would be able to do away with low pass filters entirely, and NOT suffer the consequences of moire and other aliasing. Oversampling could do away with a whole lot of issues, eliminate the complaints of people who incessently pixel peep, etc. The frequency of photon shot noise would drop to well below the smallest resolvable element of detail. 

To me, there is absolutely no reason to not use the highest resolution sensor you can get your hands on. As I stated in my previous reply...noise is relative to unit area. Average up whatever ratio of smaller pixels equal the area of a larger pixel, and you will have the same noise (all else being equal). I would much rather oversample my lens by a factor of two to three, than always be undersampling it. I'd MUCH rather have the frequency of photon shot noise be significantly higher than the frequency of the smallest resolvable detail, as then, it would simply be a matter of course to downsample by 2-3x for every single photo. Then, the smallest resolvable detail is roughly pixel-sized, and noise is 1.4-1.7x lower.


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## jrista (Aug 10, 2014)

scyrene said:


> Is that software Windows-only? I did a bit of searching, and couldn't find system requirements anywhere. For some reason, most of this sort of software doesn't run on Macs, so I had to use the only stacker I could find that did, called 'Keith's Image Stacker'. It's pretty good but I have no understanding of how different modes produce different results. I guess I should read up on it more.



Yeah, windows is pretty much the operating system of choice for astrophotography software. There are some new apps available for iOS devices, but overall, not much of the software we use runs on Macs. I think most astrophotographers either use a dual-boot (virtualization tends to be problematic and too slow) with macs so they can run windows when they need to...or, they simply have a windows based laptop for their astrophotography stuff. 

If your interested in AP, then I highly recommend you pick up a windows box of some kind. The vast majority of the software out there, like BackyardEOS, is only available for windows. 



scyrene said:


> As for video - this is a question I've had for a while. Even HD video is only 2MP. No matter how much resolution you're gaining through stacking, surely you're losing 90% (of the 5DIII's potential) versus stills? Any thoughts? When I stacked my moon (I've included a crop of a much reduced-size below) I had to shoot lots of stills manually and use those instead. You're clearly doing something better though, as you seem to be pulling out a similar level of detail even though I was at a much higher focal length (5600mm).



BackyardEOS has some unique features. It seems to be able to use the 5x and 10x zoom features of live view, then it records a 720p video from those zoomed in views. So, your actually getting more resolution than if you recorded a 720p video at 1x. 

For superresolution algorithms to work, you need your frames to be pretty close together. You want some separation, a minimal mount of time to allow for the subject to "jitter" between frames, as it's the jitter that allows an algorithm like drizzle to work in the first place. 

At 5600mm, you should be able to pull out some extreme detail of a small area of the moon's surface. I'd love to have 5600mm at my disposal!  If you pick up a windows laptop, install BackyardEOS, and play around with the planetary imaging feature...you'll start to see how it all works, and you'll start getting amazing results.


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## jrista (Aug 10, 2014)

weixing said:


> Anyway, the sky is cloudy and the bird is under the shade... so I think the details are a bit more difficult to resolve under this flat lighting condition.



For sure, flat lighting can indeed make it difficult to resolve fine detail...there just isn't any shading for it. I'd be interested to see you redo the test with better lighting. It's nice having a cooporative bird as a subject for that...none of the birds around here, except maybe Night Herons, are willing to remain still for long periods of time, but they are also very jittery, and the slightest thing sets them aflight. 

If you get another chance during better light, I'd love to see you try again. There probably isn't much of a resolving power difference between the two at high ISO...however I would expect the 6D to take the lead in overall IQ.


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## Act444 (Aug 10, 2014)

58Special said:


> I use both the 5D mk III and the 7D. I like have both, it is like have two sets of lenses. That being said if i am close enough i will always go to the 5D.



Same here. If I am not reach-limited, it will almost always be the 5D/6D. If I am, then the 7D offers more reach (at the cost of more noise).


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## jrista (Aug 10, 2014)

Act444 said:


> 58Special said:
> 
> 
> > I use both the 5D mk III and the 7D. I like have both, it is like have two sets of lenses. That being said if i am close enough i will always go to the 5D.
> ...



I would be really interested in seeing the difference between the 7D, 70D, and a 5D III/6D in a reach limited situation. The 7D is old tech, so it is going to be noisier. Theoretically, with sensors that use the same generation of technology, in a reach-limited situation the noise should not be different once the results are normalized. I am willing to bet good money that the 70D performs markedly better than the 7D in such a situation, and when downsampled to the same size as the 5D III, there would not be any significant difference in noise.


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## Lee Jay (Aug 10, 2014)

AlanF said:


> Lee Jay said:
> 
> 
> > AlanF said:
> ...



Nope, you're still off the rails. Smaller pixels can and often do have the same DR as bigger pixels, in good light. Bigger pixels tend to win in extremely photon starved conditions for secondary reasons but we're not talking about those extremes here.

Look at it this way. If you slice up one pixel into four, what have you done? You've got the same DR because read noise drops with well capacity. You've got smaller wells but they collect from a smaller area so they fill at the same rate. You're still collecting all the same light so you've got the same SnR due to shot noise. All you've really done is increase detail. If you want that detail, you can have it. If you don't, you can be stupid and block average those four pixels back down into one big one. Or, you can apply far more sophisticated noise reduction techniques than simple block averaging and end up with both more detail and less noise.


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## scyrene (Aug 10, 2014)

jrista said:


> scyrene said:
> 
> 
> > Is that software Windows-only? I did a bit of searching, and couldn't find system requirements anywhere. For some reason, most of this sort of software doesn't run on Macs, so I had to use the only stacker I could find that did, called 'Keith's Image Stacker'. It's pretty good but I have no understanding of how different modes produce different results. I guess I should read up on it more.
> ...



Thanks! I have an old desktop PC, I might see if I can use that for some of this. The primary problems at that focal length without a tracker (I have a tracking mount, but it can't take the weight of the supertelephoto) are wobble (even the slightest breeze catches the lens) and especially the movement of the moon across the frame.

I don't want to bog you down if it's a huge subject, but what is drizzle roughly, and why does a gap between frames make it less effective? Since the atmospheric distortion is random. Once the frames are aligned, how can the software tell whether they were taken milliseconds or minutes apart?


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## LetTheRightLensIn (Aug 10, 2014)

MichaelHodges said:


> LetTheRightLensIn said:
> 
> 
> > You won't?? Even if you use say a 7D and a 5D2 and the 7D sensor is more efficient at collecting and converting photons per area of surface than the 5D2?? With the 7D you can chose to get either: more detail (unless conditions are super bad) and more noise OR slightly better detail with less de-bayer and other artifacts and slightly better noise (if you view or convert to same scale as the 5D2).
> ...



Yeah but we are not talking about the entire frame on target, we are talking reach limited. Sure, if you are close enough to frame the animal as you like on a FF then sure that does much better, but we are talking reach limited, so the animal fills the same amount of sensor areas on either sensor and in that case it does work exactly that way.




> In these cases, noise is the bottleneck.



Depends upon what you mean by these cases. If you simply mean near sunset and just after sunrise in general, than that is not true. A 7D always does at least a trace better than a 5D2 for instance even then WHEN FULLY REACH LIMITED, and since that is a scenario that exists and is not even all that rare, it is definitly not true in general that the FF always does better than the 7D even under crepuscular creeping time for animals.


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## LetTheRightLensIn (Aug 10, 2014)

docsmith said:


> And I make this post knowing this thread is titled "The Reach War," but I was a little surprised that no one else had yet brought up that the differences between the 5DIII and 7D (or 70D) is about more than reach and noise.



You answered your own question because the thread is title reach war. So why on earth should it get into discussions of which grip is nicer or what AF is better or whatnot? At that point you may as well start talking about which dish of fish tastes best.


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## LetTheRightLensIn (Aug 10, 2014)

MichaelHodges said:


> jrista said:
> 
> 
> > Regarding birds and DR...to be honest, I have not found that dynamic range is the issue when photographing birds.
> ...



Personally I encounter DR issues less for wildlife than for landscapes by far and away (of course I also shoot wildlife a lot less than landscapes  ). That said there are times where interior forest dappled lighting on say turkeys or pileated woodpeckers or whatnot makes it tricky, at times even with small birds, they can perch in a way that the head is glowing and the body in deep shade and it can be rough going, so yeah it can definitely happen that more DR would definitely be useful.

Also, many more wildlife shots, in my, are taken beyond ISO400 and that is when the DR differences start to lessen between brands. Once you are shooting at ISO1600 it's really not much between them, yeah the sony still does a trace better but it's nothing to bother about then and even at ISO800 while definitely there it's no longer night and day.

That said, sure more DR for wildlife shooting or sports would be welcomed too of course, no doubt.

Oh, also sometimes you get surprised and have just a random isntant for a shot and maybe can't dial in exposure perfectly, with more DR you can rescue underexposed shots much more easily.


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## jrista (Aug 10, 2014)

scyrene said:


> I don't want to bog you down if it's a huge subject, but what is drizzle roughly, and why does a gap between frames make it less effective? Since the atmospheric distortion is random. Once the frames are aligned, how can the software tell whether they were taken milliseconds or minutes apart?



It isn't so much the gap between frames as the total frame count. It's a lot, lot easier to get thousands of frames when using video. When you take them one at a time, there is a fairly significant overhead, an overhead that could last the span of several frames. Using video cuts down that overhead significantly. For superresolution to be effective, you actually don't want all the frames to be perfectly aligned...you want very very slight variations between each frame, as the algorithm uses those differences to enhance resolution and "see" past things like atmospheric turbulence, diffraction, optical aberrations, etc. 

You could still do superresolution with individual still frames. You would just need several times as much time to gather enough frames for it to be effective. (Although, if there is enough movement of the subject between frames, as is the case without tracking...that can actually be too much movement. You want small movements between frames, but otherwise have the subject remain generally stationary...if it's drifting across the frame, then you first do have to align, and alignment might result in everything being TOO consistent across frames, thereby reducing the effectiveness of the superres algorithm.) This is particularly true when a superres algorithm is used in conjunction with a stacking algorithm and other algorithms, as is the case with planetary integration software, as those programs will drop a considerable number of frames that do not meet certain quality criteria. Remember, the goal, with the moon...or mars...or any other planet, is to take only the frames from those moments when seeing clears enough that the detail shows through really well. So, if you can take 100 still frames in 5 minutes, or 1000 video frames in 30 seconds, well, your going to choose video.


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## jrista (Aug 10, 2014)

LetTheRightLensIn said:


> That said, sure more DR for wildlife shooting or sports would be welcomed too of course, no doubt.



Totally agree here. Having more DR is not a problem, and can make some of the rarer but tougher situations, like the ones you described, easier to deal with. 

To that end, I think Magic Lantern is a HUGE bonus for Canon shooters, as (at least so far, with the 6D) they have managed to increase high ISO DR to levels that were previously only attainable at ISO 400 and below on most cameras (the notable exceptions being 1DX and D4).


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## LetTheRightLensIn (Aug 10, 2014)

AlanF said:


> jrista said:
> 
> 
> > serendipidy said:
> ...



Actually it works out that smaller pixels tend to actually help dynamic range overall although hurt say mid-tone SNR. However, the degree to which they hurt SNR is pretty modest in the typical denisities we are comparing with current cameras. If you compared a 180MP APS-C to an 8MP APS_C the 120MP one might start to suffer enough to care with the current tech, BSI and such might help that though. But for say a 36MP FF vs a 12MP FF the difference is so minor that it's really nothing to bother about, it depends on the exact tech, but let us even say 1/8th of a stop for kicks, who really cares.


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## scyrene (Aug 10, 2014)

jrista said:


> scyrene said:
> 
> 
> > I don't want to bog you down if it's a huge subject, but what is drizzle roughly, and why does a gap between frames make it less effective? Since the atmospheric distortion is random. Once the frames are aligned, how can the software tell whether they were taken milliseconds or minutes apart?
> ...



Thanks again  I can try the video option for the moon at least, where I can pull down the focal length and still have it fill the frame. Since I downsize the final images from stills anyway, it probably edges in favour of the big stack. But for tinier subjects, like planets, unless I went with your (amazing sounding!) magnified video option, I'd stick with manually-taken frames. I managed to take 100-200 before getting bored


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## LetTheRightLensIn (Aug 10, 2014)

jrista said:


> LetTheRightLensIn said:
> 
> 
> > That said, sure more DR for wildlife shooting or sports would be welcomed too of course, no doubt.
> ...



doesn't that lose half the res though? that would be bad for reach limited wildlife in particular I'd think
although perhaps for the parts of the body in shade the detail is not as often critical?


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## LetTheRightLensIn (Aug 10, 2014)

weixing said:


> Hi,
> Today, I do a compare shots on FF vs APS-C on a real bird under real life condition... only manage to try out ISO 1600 and ISO 3200 as start to rain very heavily after this. I just open them using lightroom 4, took a screenshot, paste on paint and saved as jpeg.
> *Test Condition*
> *Camera:* Canon 6D (left) vs Canon 60D (right)
> ...



despite a relatively low contrast subject and a lens said to be fairly soft at the extreme end (and perhaps other issues for AF or shake for all we know) I still saw that the 60D was giving it more details, comparing like that can sometimes give a slight apparent advantage to the lower density camera since the eye tends to confused crispness with detail



> PS: The CanonRumors website seem to scale down the screenshot image (actual size is 1920 x 1080) to fit the website frame... to view at actual size, need to click on the image and using the scroll bar below the post to scroll through the image... or is there a setting to show the image actual size??



yeah a real drag, I ended up just right clicking saving to my computer and then viewing with an imager at 100% view


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## LetTheRightLensIn (Aug 10, 2014)

jrista said:


> In crepuscular light, the low light around sunrise and sunset, you are NOT going to be using ISO 100 or 200. As you say, your going to be up at ISO 12800. You need the high ISO so you can maintain a high shutter rate, so you can freeze enough motion to get an acceptable image. There are times during the day when you can capture wildlife out and about, but the best times are indeed during the crepuscular hours of the day.
> 
> Just for reference, here are the dynamic range values for four key cameras at ISO 12800:
> 
> ...



Good points in general, although the wrong specific data.
The actual values should have been listed as:

ISO12,800 DR
D810: 8.13
5D3: 8.25
1DX: 8.99

1DX with a 0.86 stop advantage over D810.

So there is nothing between it for the 5D3 vs D810, although the 1DX does give you nearly a stop more which is nice. In other terms it gets tricky, smaller pixels give finer grain which bothers the eye less and allow you to apply more advanced NR techniques. I'm not sure how banding and glow and such look between the nikon and canon at 12,800. So perhaps the real feel of the difference for some shots would be more or perhaps less.

(I know you asked to not have this brought up again, but since you went to DxO, there is no choice. You can't about smaller pixels not hurting and then suddenly when you go to DxO chose the wrong setting that does penalize smaller pixels.)



> At ISO 6400, we have:



we actually have:
D810 9.08
5D3 9.07
1Dx 9.88

etc.


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## neuroanatomist (Aug 10, 2014)

LetTheRightLensIn said:


> jrista said:
> 
> 
> > In crepuscular light, the low light around sunrise and sunset, you are NOT going to be using ISO 100 or 200. As you say, your going to be up at ISO 12800. You need the high ISO so you can maintain a high shutter rate, so you can freeze enough motion to get an acceptable image. There are times during the day when you can capture wildlife out and about, but the best times are indeed during the crepuscular hours of the day.
> ...



Interesting. Please tell us what RAW converter you use that allows you to edit RAW files downscaled to 8 MP. All of them I've used only allow RAW editing at full resolution. : : :


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## jrista (Aug 10, 2014)

LetTheRightLensIn said:


> jrista said:
> 
> 
> > LetTheRightLensIn said:
> ...



I did not think so...but I could be wrong. If it does, then you are right, it wouldn't be good in a reach-limited situation.


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## jrista (Aug 10, 2014)

LetTheRightLensIn said:


> jrista said:
> 
> 
> > In crepuscular light, the low light around sunrise and sunset, you are NOT going to be using ISO 100 or 200. As you say, your going to be up at ISO 12800. You need the high ISO so you can maintain a high shutter rate, so you can freeze enough motion to get an acceptable image. There are times during the day when you can capture wildlife out and about, but the best times are indeed during the crepuscular hours of the day.
> ...



Here is my reference:

http://sensorgen.info/CanonEOS-1D_X.html
http://sensorgen.info/CanonEOS_5D_MkIII.html
http://sensorgen.info/NikonD800.html
http://sensorgen.info/NikonD810.html


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## AlanF (Aug 11, 2014)

jrista said:


> AlanF said:
> 
> 
> > jrista said:
> ...



Jon
I am using the same source of information that you quoted for number of pixels on target - Clark.

http://www.clarkvision.com/articles/does.pixel.size.matter/

Quote: "The images in Figures 10 and 11 illustrate that combining pixels does not equal a single image. The concept of a camera with many small pixels that are averaged to simulate a camera with larger pixels with the same sensor size simply does not work for very low light/high ISO conditions. This is due to the contribution of read and electronics noise to the image. Again this points to sensors with larger pixels to deliver better image quality in high ISO and low light situations."


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## AlanF (Aug 11, 2014)

jrista said:


> AlanF said:
> 
> 
> > +1 My biggest mistakes are when my camera is set for point exposure for birds against a normal background and one flies by against the sky and I don't have time to dial in +2 ev to compensate or vice versa. Two more stops of DR would solve those problems.
> ...



Autofocus is not _necessary_, automatic metering is not _necessary_, IS is not _necessary_. The fact is that having those features makes it a lot easier, and having an extra couple of stops of DR would also make it easier. It is not a question of lack of skill but having a camera that eliminates one more variable.


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## jrista (Aug 11, 2014)

AlanF said:


> Jon
> I am using the same source of information that you quoted for number of pixels on target - Clark.
> 
> http://www.clarkvision.com/articles/does.pixel.size.matter/
> ...



I think your misinterpreting what he is saying. He isn't saying that read noise increases as pixels get smaller. He is saying that read noise represents a larger percentage of the image signal at higher ISO than at lower ISO, and the higher SNR of larger pixels offsets that. That is a true statement.

There are other factors to consider about high ISO, though. I think it was Lee Jay who stated it earlier in the thread, but read noise is lower with smaller pixels. Look at Sensorgen.info, which is empirical data, and look at the read noise levels (that is ALL read noise...dark current contribution as well as downstream electronics contributions). The 7D has ~8e- RN @ ISO 100, while the 5D III has ~33e- RN @ ISO 100. Since you can fit 2.1 7D pixels into the space of a single 5D III pixel, the "equivalent RN" of binned pixels would be ~16.8e- RN, still half what the 5D III has (I really don't understand why Canon's newer sensors have such high read noise...their RN levels are REALLY bad...but maybe it's a tradeoff they make for their high frame rates for the pixel count or something. I can't wait till Canon moves to an on-die CP-ADC design...) I used the word binned there, because it's important. If you average pixels together in post, the random component of read noise drops. Only the non-random component of read noise will strengthen. Canon in general has a handicap there...they have some strong pattern noise at low ISO on the 7D, and even some still on the 5D III. At least it only really shows up at lower ISO settings. 

From a read noise standpoint, the 7D is actually very good. Some of the BEST ultra low noise CCD astro sensors on the market, one of which is the Sony ICX694, have ~5e- RN. At 5e- RN, that is one of the lowest read noise levels on the planet. There is a table of read noise levels on an astro site somewhere (I don't have the link handy now), and the lowest standard-gain RN I've ever seen was 4.5e-. Most DSLRs seem to bottom out at around ~3e- at high ISO (at least, according to Sensorgen.info...Clark's results are a little more linear, and his results indicate RN levels drop to as little as ~2e- at their lowest). Regardless of whether RN is 3e- or 2e-, it's EXTREMELY LOW, and a minor contributor to overall high ISO noise in general.

Larger sensors perform better at high ISO because they have the potential to gather more light in total. This thread is all about the reach limitation, in which case, framing identically is not an option. When framing identically is not an option, _*** assuming all else is equal ***_ (I'm REALLY trying to emphasis this point, because the 7D and 5D III are not "all else equal"...the 70D and 5D III would be on more equal technological footing), then pixel size does very little to nothing to improve IQ. There is the fill factor issue to consider...at some point, you reach a small pixel size where, even with a small transistor/wire size, the sheer number of pixels necessitates contributing a meaningful amount of sensor space to that wiring unless you use a BSI design. If the small pixels are small enough that fill factor reduces total photodiode area by a meaningful amount, then averaging pixels is not going to be completely capable of normalizing noise.

The primary reason full frame cameras do better in low light is because they can gather more light in total. If I frame my subject identically with an APS-C and FF camera, then the FF camera is gathering more light in total for my subject. Once normalized, the noise will be lower with the full frame sensor. Because the subject is _relative *to *the frame_, instead of _absolute *within *the frame_. I could use two full frame cameras, one with larger pixels and one with smaller pixels. So long as I frame identically, all else being equal, the normalized results will exhibit the same noise. The only difference would be that one image is crisper and sharper than the other...and that would be the FF sensor with more, smaller pixels. 

I kind of wish I had a 70D at my disposal now, so I could demonstrate with equipment of equivalent technology generation. The 70D has about 6000e- more FWC than the 7D, which is significant, considering the 7D only had about 20ke- to start with. (It's a 30% increase.) Averaging a 70D image to the same size as a 5D III image should have the effect of reducing noise to very similar levels...close enough that you would have to scrutinize to identify any differences. 



AlanF said:


> jrista said:
> 
> 
> > AlanF said:
> ...



Well, I think were getting into semantics now, so I won't really press the issue. Yes, having more DR can certainly make things easier, but good technique can totally eliminate the need, and can be just as easy in practice. That's what I was trying to say.


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## MichaelHodges (Aug 11, 2014)

LetTheRightLensIn said:


> Yeah but we are not talking about the entire frame on target, we are talking reach limited. Sure, if you are close enough to frame the animal as you like on a FF then sure that does much better, but we are talking reach limited, so the animal fills the same amount of sensor areas on either sensor and in that case it does work exactly that way.



I shoot for months at a time with FF and APS-C in the wilderness. "Pixels on target" does not matter if the noise is too high. The APS-C simply has to be set aside in these instances.




> Depends upon what you mean by these cases. If you simply mean near sunset and just after sunrise in general, than that is not true. A 7D always does at least a trace better than a 5D2 for instance even then WHEN FULLY REACH LIMITED, and since that is a scenario that exists and is not even all that rare, it is definitly not true in general that the FF always does better than the 7D even under crepuscular creeping time for animals.




As someone who has spent countless hours using both formats side by side in the same conditions, I can tell you the full frame images will be superior to 7D images in crepuscular hours for big game. ISO 3200 on the 6D or 5DIII is significantly better than ISO 3200 on the 7D.


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## MichaelHodges (Aug 11, 2014)

jrista said:


> Yes, having more DR can certainly make things easier, but good technique can totally eliminate the need




It can't, unfortunately. Actual wildlife chooses the light. The photog has to adapt to this. 

We can do our best to maintain desired angles and minimize the requirement for dynamic range, bu there will always be situations when shooting wild animals where increased dynamic range is beneficial.

And I agree that technique is important. But nature doesn't care what your camera settings are. If you are in the field long enough, she's going to throw you surprises. These are almost always the more interesting photos, IMHO. Yeah I can spend days filming a hawk's face up close while it perches, or film animals feeding. 

But what I really want to capture are those magic moments out of nowhere, the moments that tell a vivid story in one, simple frame. Here, we need all the tools in the tool box, and increased dynamic range can mean the difference between a wall hanger and the delete button.


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## MichaelHodges (Aug 11, 2014)

LetTheRightLensIn said:


> *Also, many more wildlife shots, in my, are taken beyond ISO400 and that is when the DR differences start to lessen between brands. *Once you are shooting at ISO1600 it's really not much between them, yeah the sony still does a trace better but it's nothing to bother about then and even at ISO800 while definitely there it's no longer night and day.




This is a good point. I have not shot the FF Nikons at higher ISO's, nor tested the shadow lifting capability there. If the lifting abilities are similar at ISO's above 400, there's not much point unless you're doing landscape.


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## MichaelHodges (Aug 11, 2014)

AlanF said:


> Autofocus is not _necessary_, automatic metering is not _necessary_, IS is not _necessary_. The fact is that having those features makes it a lot easier, and having an extra couple of stops of DR would also make it easier. It is not a question of lack of skill but having a camera that eliminates one more variable.



Yep.


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## jrista (Aug 11, 2014)

MichaelHodges said:


> jrista said:
> 
> 
> > Yes, having more DR can certainly make things easier, but good technique can totally eliminate the need
> ...



I would say the results of many professional bird and wildlife photographers, who do exactly what you describe for a living, and use Canon cameras to create phenomenal works of art, would prove this post to be fundamentally wrong.


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## AlanF (Aug 11, 2014)

I actually had at one stage a 5dIII, 70D and 7D (with 300mm f/2.8II+2xTCIII) and tested them in good light by photographing lapwings on a raft at extreme distance. All the following shots are 100% crops, processed identically in DxO and with PRIME noise reduction, that virtually eliminates noise. Top is the 70D, which is 671x711 pixels; middle 7D; middle 7D, which is 643x655 pixels; bottom is 5DII, which is 483x447 pixels. In the next post, the 70D is tested against the 5DIII. Under these reach limited conditions, there seems little, if any advantage of using the APS-C.


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## AlanF (Aug 11, 2014)

Really pushing it to catch a bittern a couple of 100 yards away. Again 100% crops, where the bird is just a few hundred pixels. The 70D is at the top. 5DIII at the bottom. There is no dramatic difference added by the extra reach. I am happy equally using either the 5DIII or the 70D in good light. However, the 5DIII is more tolerant to poorer light and is more resistant to camera shake for my hand held shots at lower shutter speeds.


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## MichaelHodges (Aug 11, 2014)

jrista said:


> I would say the results of many professional bird and wildlife photographers, who do exactly what you describe for a living, and use Canon cameras to create phenomenal works of art, would prove this post to be fundamentally wrong.



Don't hide behind platitudes, Jrista. Make the case for yourself. 

This is your quote:



> Anyway, when it comes to bird and wildlife photography, dynamic range is just not an issue.



It's a huge issue. Unless you're shooting with flash, or baiting animals (two practices I find unethical), DR is going to play a huge role.


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## MichaelHodges (Aug 11, 2014)

AlanF said:


> Really pushing it to catch a bittern a couple of 100 yards away. Again 100% crops, where the bird is just a few hundred pixels. The 70D is at the top. 5DIII at the bottom. There is no dramatic difference added by the extra reach. I am happy equally using either the 5DIII or the 70D in good light. H*owever, the 5DIII is more tolerant to poorer light and is more resistant to camera shake for my hand held shots at lower shutter speeds.*



My experience as well. But I will add that the 70D is a *significant* step up in IQ over the 7D.


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## jrista (Aug 11, 2014)

MichaelHodges said:


> jrista said:
> 
> 
> > I would say the results of many professional bird and wildlife photographers, who do exactly what you describe for a living, and use Canon cameras to create phenomenal works of art, would prove this post to be fundamentally wrong.
> ...



We disagree here. It's as simple as that. I could point you to my own work, at http://jonrista.com (since you insist I make the case myself), as well as the work of numerous professional bird and wildlife photographers who have been using Canon gear for years, and never seem to complain about the lack of DR at the very high ISO settings they use. Not only that, their work is phenomenal. 

You have to understand, unless you are talking about shooting wildlife at ISO 100 and 200, there is very little difference in DR at higher ISO settings, with the exception of the 1D X (which has a good stop and a half ADVANTAGE at VERY high ISO settings.) Did you miss my post where I shared the DR numbers from sensorgen for the D810, D800, 5D III, and 1D X? I thought that would have put the issue to rest. Are you talking about wildlife photography shot at ISO 100 or 200, or are we talking about your crepuscular light wildlife photography, at ISO 12800?

What camera out there, anywhere, offers any kind of significant advantage (and by that, I mean the 2+ stops DR improvement the Sony Exmor cameras get at ISO 100) in DR over any other camera, AT HIGH ISO? I mean, if such a thing exists...I'd like to know about it...but frankly, aside from the 1D X at ISO 12800, 25600, and 51200 (which is actually less than a 2-stop difference compared to any other camera), I don't think it does.


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## jrista (Aug 11, 2014)

AlanF said:


> I actually had at one stage a 5dIII, 70D and 7D (with 300mm f/2.8II+2xTCIII) and tested them in good light by photographing lapwings on a raft at extreme distance. All the following shots are 100% crops, processed identically in DxO and with PRIME noise reduction, that virtually eliminates noise. Top is the 70D, which is 671x711 pixels; middle 7D; middle 7D, which is 643x655 pixels; bottom is 5DII, which is 483x447 pixels. In the next post, the 70D is tested against the 5DIII. Under these reach limited conditions, there seems little, if any advantage of using the APS-C.



Just off a cursory glance, it looks like the 5D III is better lit. If you don't mind, I'm going to downsample the middle 7D bird to the same size as the 5D III bird, so we can compare properly normalized results.


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## AlanF (Aug 11, 2014)

jrista said:


> AlanF said:
> 
> 
> > I actually had at one stage a 5dIII, 70D and 7D (with 300mm f/2.8II+2xTCIII) and tested them in good light by photographing lapwings on a raft at extreme distance. All the following shots are 100% crops, processed identically in DxO and with PRIME noise reduction, that virtually eliminates noise. Top is the 70D, which is 671x711 pixels; middle 7D; middle 7D, which is 643x655 pixels; bottom is 5DII, which is 483x447 pixels. In the next post, the 70D is tested against the 5DIII. Under these reach limited conditions, there seems little, if any advantage of using the APS-C.
> ...


Please do so - I posted them to be used.


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## RustyTheGeek (Aug 11, 2014)

MichaelHodges said:


> My experience as well. But I will add that the 70D is a *significant* step up in IQ over the 7D.



Which is why my 60D (same sensor as the 7D) doesn't see much use any more for swimming pictures after I got my 5D3. And why I've decided to not buy a less expensive 7D now even though it's a great camera. I'm going to wait to see what the 7D2 has to offer and how stupid the price is. Then I'll probably just get a 70D anyway.


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## jrista (Aug 11, 2014)

Here is a normalized comparison of Alan's lapwing images:







I think the IQ of the 7D image has improved to the same level as the 5D III image for the subject. There is still more background noise, however I averaged the background with a median filter and measured the levels. The 7D image has an average level of 99-101 (RGB channels), while the 5D III image has an average level of 106/125/150 (RGB Channels). The brighter background level is helping the 5D III image a bit from a noise standpoint. 

(Note, noise is worth in both images here due to GIF format.)


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## MichaelHodges (Aug 11, 2014)

jrista said:


> What camera out there, anywhere, offers any kind of significant advantage (and by that, I mean the 2+ stops DR improvement the Sony Exmor cameras get at ISO 100) in DR over any other camera, AT HIGH ISO? I mean, if such a thing exists...I'd like to know about it...but frankly, aside from the 1D X at ISO 12800, 25600, and 51200 (which is actually less than a 2-stop difference compared to any other camera), I don't think it does.




The goal posts seem to be shifting. The discussion above was about dynamic range in general for wildlife. Not specific brands. 

I think developing this tech is just as important (regardless of who develops it at higher ISO's) as IS and other improvements within the context of wildlife photography.


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## jrista (Aug 11, 2014)

MichaelHodges said:


> jrista said:
> 
> 
> > What camera out there, anywhere, offers any kind of significant advantage (and by that, I mean the 2+ stops DR improvement the Sony Exmor cameras get at ISO 100) in DR over any other camera, AT HIGH ISO? I mean, if such a thing exists...I'd like to know about it...but frankly, aside from the 1D X at ISO 12800, 25600, and 51200 (which is actually less than a 2-stop difference compared to any other camera), I don't think it does.
> ...



Well, DR discussions usually involve just two or three specific brands, and the tone of the conversation is always the same. I guess I assumed, apologies.

However, you handily skipped past the FAR more important part of the post you quoted. I think it's an important discussion, and I believe your answers are important, because fundamentally, at high ISO, the available dynamic range is ultimately bound by physics, not technology. So, if you don't mind:



> We disagree here. It's as simple as that. I could point you to my own work, at http://jonrista.com (since you insist I make the case myself), as well as the work of numerous professional bird and wildlife photographers who have been using Canon gear for years, and never seem to complain about the lack of DR at the very high ISO settings they use. Not only that, their work is phenomenal.
> 
> You have to understand, unless you are talking about shooting wildlife at ISO 100 and 200, there is very little difference in DR at higher ISO settings, with the exception of the 1D X (which has a good stop and a half ADVANTAGE at VERY high ISO settings.) Did you miss my post where I shared the DR numbers from sensorgen for the D810, D800, 5D III, and 1D X? I thought that would have put the issue to rest. Are you talking about wildlife photography shot at ISO 100 or 200, or are we talking about your crepuscular light wildlife photography, at ISO 12800?



Could you answer the questions posed? Are you shooting wildlife at ISO 100 and 200 on a regular basis? If so, how do you reconcile that with your prior comments about crepuscular light and ISO 12800? Is there a camera out there that gets 14 stops of DR at ISO 12800? Is there a camera out there that gets more than 10 stops of DR at ISO 12800? 

At high ISO, with the exception of one or two VERY expensive cameras, there is little to no difference in dynamic range! It doesn't matter if your using a D810, an A7r, a or a 5D III. There is less than a stop difference between the lot at ISO 12800. They are all full frame cameras, and in a normalized context, they will all perform roughly the same in crepuscular light for wildlife. You can eek a bit more performance out of a 1D X or a D4, but were still very far from the 2+ stop advantage an Exmor has over most other sensors at ISO 100.

If high ISO DR is critical to your shooting style, I still think Canon has the advantage because of ML. I found the thread that discusses their high ISO DR improvements (which, on the 6D, bring you to 1D X/D4 levels of DR):

http://www.magiclantern.fm/forum/index.php?topic=10111.0

According to this thread, the high ISO DR tweak does NOT use the dual ISO technique that reduces vertical resolution...it uses a tweak of the downstream amplifier to avoid clipping the signal, thereby preserving about 1/2 a stop additional DR at all ISO levels.


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## MichaelHodges (Aug 11, 2014)

jrista said:


> Could you answer the questions posed? Are you shooting wildlife at ISO 100 and 200 on a regular basis?



If I can pull off the shutter speed, I always try to shoot at the lowest ISO. Sometimes it's ISO 6400, sometimes 100.



> If so, how do you reconcile that with your prior comments about crepuscular light and ISO 12800? Is there a camera out there that gets 14 stops of DR at ISO 12800? Is there a camera out there that gets more than 10 stops of DR at ISO 12800?
> 
> At high ISO, with the exception of one or two VERY expensive cameras, there is little to no difference in dynamic range! It doesn't matter if your using a D810, an A7r, a or a 5D III. There is less than a stop difference between the lot at ISO 12800. They are all full frame cameras, and in a normalized context, they will all perform roughly the same in crepuscular light for wildlife. You can eek a bit more performance out of a 1D X or a D4, but were still very far from the 2+ stop advantage an Exmor has over most other sensors at ISO 100.



You seem to be viewing the discussion through a "brand lens". My comments about dynamic range are within the context of shooting wildlife regardless of brand. If someone can figure out how to get the dynamic range of the Sony sensors into higher ISO's, I'll be the first in line.


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## scyrene (Aug 11, 2014)

MichaelHodges said:


> You seem to be viewing the discussion through a "brand lens". My comments about dynamic range are within the context of shooting wildlife regardless of brand. If someone can figure out how to get the dynamic range of the Sony sensors into higher ISO's, I'll be the first in line.



Hey, can you post some high DR wildlife images, please? I'd like to be able to visualise what you're talking about  Like I said way back in this thread, I assume it's partly cos you're going for big mammals rather than tiny songbirds, but I may be wrong.

And jrista, I forgot to post that moon crop when I said I would. Not that it really matters, but I'll stick it here anyway


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## MichaelHodges (Aug 11, 2014)

scyrene said:


> Hey, can you post some high DR wildlife images, please? I'd like to be able to visualise what you're talking about  Like I said way back in this thread, I assume it's partly cos you're going for big mammals rather than tiny songbirds, but I may be wrong.



I'd be happy to. This image just got picked up for a textbook run:






One of the first things I look for, above all else in wildlife photography is "animal-scapes". I find them far more interesting than nostril or "trophy" shots. This often involves using shorter telephoto lenses. And it often involves shooting in less than ideal light, and in conditions like this (eight below zero). The bison were happy as could be, though.

This was one of the rare instances when my 7D did okay. The shot is ISO 200, and obviously I'm trying to get the sunset exposure nailed perfectly while bringing up the bison shadows later in post. You can't fix a blown sky, but you can lift shadows. Well, sort of.  When lifting the shadows, the 7D annihilated detail with severe banding and noise. I was able to fix much of it with tedious post processing, but a superior sensor would have delivered a cleaner image capable of printing much larger. I had my 6D with me, but it was attached to a 300mm.

Don't get me wrong, I'm happy, but it could have been cleaner.


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## Sporgon (Aug 11, 2014)

MichaelHodges said:


> scyrene said:
> 
> 
> > Hey, can you post some high DR wildlife images, please? I'd like to be able to visualise what you're talking about  Like I said way back in this thread, I assume it's partly cos you're going for big mammals rather than tiny songbirds, but I may be wrong.
> ...



Come on Michael, stop pulling everyone's leg. You shot that on a D800 didn't you


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## Lee Jay (Aug 11, 2014)

MichaelHodges said:


> You seem to be viewing the discussion through a "brand lens". My comments about dynamic range are within the context of shooting wildlife regardless of brand. If someone can figure out how to get the dynamic range of the Sony sensors into higher ISO's, I'll be the first in line.



You'd need to reduce read noise to practically zero, and even then the problem is you might only be getting a couple of photons in each pixel in the darker areas of the frame which means you'd be really shot-noise limited.

Shot noise is effectively in the light itself. The only ways to improve it are to have better microlens fill factor (already nearing 100%), better QE (already over 50%), lower losses in the Bayer dyes (they've already done that so the next step would be to get rid of the Bayer dyes), or just getting more light (faster lenses, longer shutter periods).


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## scyrene (Aug 11, 2014)

MichaelHodges said:


> scyrene said:
> 
> 
> > Hey, can you post some high DR wildlife images, please? I'd like to be able to visualise what you're talking about  Like I said way back in this thread, I assume it's partly cos you're going for big mammals rather than tiny songbirds, but I may be wrong.
> ...



Thanks! It makes much more sense to me now. Landscapes can need a lot of DR, so an animal-in-context shot likely will, too. I usually prefer to have a much closer crop, but as I say, I don't do mammals - and I tend to go for 'textbook' composition, maybe because I'm still early in my career.

It's a moody shot. Very atmospheric.


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## MichaelHodges (Aug 11, 2014)

Sporgon said:


> Come on Michael, stop pulling everyone's leg. You shot that on a D800 didn't you



8)


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## Marsu42 (Aug 11, 2014)

jrista said:


> Why? Because the moon covered the *same absolute sensor area*. There is a difference in pixel count between the two images, but overall, *both sensors gathered exactly the same amount of light!* _That's the key there._ There is no advantage to a larger sensor if you are not utilizing that increase in sensor area.



Thanks for the great post! Two additions here from my 60d/6d experience:

1. The more sensor coverage you have (with about the same mp ff vs crop), the more you can profit from *future developments in noise reduction*. DxO's prime shows the way, and I'm sure there's going to be more developments once even more computing power is available. 

2. You're talking of reach for tele shots, with *reach for macro* there's the aspect of a) flight distance of animals and b) light occlusion by the lens (for available light or flash). That's why I still prefer my 60d for insect macros and the like even over my shiny new 6d. The 100L is as sharp as it gets on crop, so no advantage of ff here.



jrista said:


> Are you shooting wildlife at ISO 100 and 200 on a regular basis?



Me, too, esp. because *Magic Lantern's +3ev dynamic range boost* with dual_iso only works with base iso ... that's why I'm regularly using 100/800 or 100/1600 is for wildlife for shadow/sun, sunrise/sunset or catching specular highlights.


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## lexptr (Aug 13, 2014)

Thanks for the interesting test!
Sorry if I will repeat something that was already said (have no time to read all 10 pages...)
The results are not surprising for me. You have tested a very specific situation, where APS-C will show an expected advantage. An exceptional lens was used, capable to deliver a very fine detail, which was happily recorded by smaller pixels of APS-C camera. Hence you've got a better detail. It is actually very simple. And because shooting conditions was good (low ISO, moderate aperture) you had no problems with possible noise and diffraction. It is known that in some cases APS-C has advantages. Another example: some time it is better for macro, because you can get better actual magnification and deeper DOF. 
But, anyway, thanks for another point for keeping APS-C camera, after I finally will upgrade to FF!


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## jrista (Aug 13, 2014)

lexptr said:


> Thanks for the interesting test!
> Sorry if I will repeat something that was already said (have no time to read all 10 pages...)
> The results are not surprising for me. You have tested a very specific situation, where APS-C will show an expected advantage. An exceptional lens was used, capable to deliver a very fine detail, which was happily recorded by smaller pixels of APS-C camera. Hence you've got a better detail. It is actually very simple. And because shooting conditions was good (low ISO, moderate aperture) you had no problems with possible noise and diffraction. It is known that in some cases APS-C has advantages. Another example: some time it is better for macro, because you can get better actual magnification and deeper DOF.
> But, anyway, thanks for another point for keeping APS-C camera, after I finally will upgrade to FF!



The quality of the lens in this case really doesn't have much to do with it. The resolution is seeing limited, which reduces resolution much more than even diffraction. On top of that, a 2x TC was used, which also reduces resolution below the diffraction limit. If the image was diffraction limited, then yes, the 7D is going to make better use of the detail being resolved by the lens. But that was not the case...I was seeing limited. 

If I did a test where the lens was diffraction limited, the 7D would probably take a greater lead than I've demonstrated here.


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## NancyP (Aug 13, 2014)

In case people don't understand "seeing limited", this refers to atmospheric interference when viewing celestial objects like the moon. Twinkle twinkle little star - the star is a point light source to us and should be a non-twinkling dot, but air turbulence, temperature differential, humidity in air all affect (refract) the image of that dot. That's why astrophotographers stack ("average") large numbers of identical moon or planet photos.


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## Lee Jay (Aug 14, 2014)

NancyP said:


> In case people don't understand "seeing limited", this refers to atmospheric interference when viewing celestial objects like the moon. Twinkle twinkle little star - the star is a point light source to us and should be a non-twinkling dot, but air turbulence, temperature differential, humidity in air all affect (refract) the image of that dot. That's why astrophotographers stack ("average") large numbers of identical moon or planet photos.



Stacking is for reducing noise. The " lucky imaging technique" where you select the best frames from many (usually from video) is for getting around the seeing limit. You stack just those best frames to reduce noise on already high resolution images.

It's not an insignificant difference. In some cases, you can improve from a seeing limited image at 2 arc seconds to a diffraction limited one at better than half an arc second.


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## mackguyver (Aug 14, 2014)

Lee Jay said:


> NancyP said:
> 
> 
> > In case people don't understand "seeing limited", this refers to atmospheric interference when viewing celestial objects like the moon. Twinkle twinkle little star - the star is a point light source to us and should be a non-twinkling dot, but air turbulence, temperature differential, humidity in air all affect (refract) the image of that dot. That's why astrophotographers stack ("average") large numbers of identical moon or planet photos.
> ...


Astrophotography seems _very_ complicated - making the results that jrista and others share all the more impressive.


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## jrista (Aug 14, 2014)

mackguyver said:


> Lee Jay said:
> 
> 
> > NancyP said:
> ...



It's pretty complicated, for sure. It should be noted seeing limited spot size is rarely as good as 2" (arcseconds). Because of seeing in Colorado, it's usually somewhere between 3.8-4.1", even worse at times. In most of the US, seeing-limited spot size is usually a little over 3"...if you have a 2" seeing limited spot size, your seeing is pretty good. If you have seeing limited spots that are smaller than 1.5", your seeing is excellent. Assuming you use drizzling to increase the resolution beyond that, if you used full 3x drizzling, resolution could improve to 0.5". With seeing of 3.8", 3x drizzling might be able to improve resolution to 1.3" (you really need a LOT of frames to achieve that, though).

Also, getting diffraction-limited images at less than half an arcsecond is also rare. The longer the scope, the greater the magnification...very long scopes (when you add a 2x or 3x barlow, for example) are diffraction limited, but they magnify the spot so much that you can actually see the "waves", or the rings of the airy disk around the central star's peak (also only possible with truly excellent seeing...less than that, and the star jumps around and gets warped, so you still can't get a diffraction limited spot.) The central peak of a star might be 0.5", but the whole airy disk is still there an visible, so the actual diffraction-limited resolution is less than 0.5". With most telescopes, a diffraction limited star is larger than 0.5". With some of the best telescopes on earth, such as a Planewave or an RCOS, you might get on-axis diffraction limited spot at ~0.4", and off-axis (corner) diffraction limited spot at ~0.6". Those telescopes cost tens of thousands of dollars.

With a lens like mine, or your average astrograph refractors or RCs, your on-axis diffraction limited spot is usually going to be quite a bit larger than 0.5" in the absolute best of conditions. Any off-axis spots are going to suffer from some kind of aberration...astigmatism, coma, field curvature, etc. Corner spot size in many scopes can be quite large, and often looks like little comets or out of focus blur.


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## Lee Jay (Aug 14, 2014)

Yes...the numbers I was giving were for the best of conditions. I've had seeing that was so bad it looked like I was looking through a jet engine wake!


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## wickidwombat (Aug 15, 2014)

Marsu42 said:


> jrista said:
> 
> 
> > Why? Because the moon covered the *same absolute sensor area*. There is a difference in pixel count between the two images, but overall, *both sensors gathered exactly the same amount of light!* _That's the key there._ There is no advantage to a larger sensor if you are not utilizing that increase in sensor area.
> ...


can you post a detailed description of how to use and process dual iso? ive tried it but the results are not good


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## Marsu42 (Aug 21, 2014)

wickidwombat said:


> can you post a detailed description of how to use and process dual iso? ive tried it but the results are not good



Well, you could have a look at the ML site but for a fellow CR regular here it goes 

1. obviously: inststall ML
2. probably less obvious: enable "dual_iso" module in the ML menu

3. in the expo menu, enable "dual iso" and set the 2nd iso to use. I usually set the camera to fixed iso 100 and set ML to either 800 (=2.5ev gained) or when push comes to shove 1600 (=3.0ev gained). Then I expose for the highlights, i.e. I dial down ec to -2 or -3 until the highlights aren't clipped anymore - check the ML raw histogram for that.

4. you end up with an interlaced file DUALxyz.cr2 (if you've set the prefix option in the dual_iso menu). You then have to run a post-processing utility "cr2hdr" on the file to get a non-interlaced 16bit raw dng you can import into your postprocessing software.

Get cr2hdr.exe here (Mac/Linux also available somewhere): http://www.magiclantern.fm/forum/?topic=7139.0

The drawbacks of using dual_iso are:
a) it's harder to check for focus in camera because the image is interlaced
b) it's impossible to check for colors because they are screwed before processing with cr2hdr
c) postprocessing hassle, esp. time required for cr2hdr processing
d) dual file storage because you want to keep around the original cr2 in case cr2hdr receives further improvements
e) results usually needs manual wb (esp. tint) setting even though cr2hdr tries to autodetect it
f) if you use it regularly, you really wish you'd have a Nikon with native 14ev @base iso

All in all, I tend to use dual_iso very often, it simply saves me all the 2x brackets I used to do before and had to assemble with a hdr software, accepting the problem with frame differences like moving leaves or grass. I cannot believe how limiting it was to be stuck with the 10.5ev of my old 60d now that I can use 14+ev to capture shadows and bright sunlight in one frame.


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## eninja (Sep 5, 2014)

Does anyone can list down "remarks and conclusion or rules in layman's term", targeted for people who got two bodies FF and APS-C to be able to get better quality photo?

To rephrase it, if one got two bodies but only one lens without the photographer moving closer to subject. which body should I use to conserve image quality?

If ISO to be use is less than 800. should I use 6D and crop it or I better use my 700D?
On the other hand, if ISO to be use is >1600. should I use 6D and crop it or I better use my 700D?

This thread is so picture quality geek into sub pixel level, i dont even know if my question is appropriate. 

Thanks in advance.


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## jrista (Sep 5, 2014)

eninja said:


> Does anyone can list down "remarks and conclusion or rules in layman's term", targeted for people who got two bodies FF and APS-C to be able to get better quality photo?
> 
> To rephrase it, if one got two bodies but only one lens without the photographer moving closer to subject. which body should I use to conserve image quality?
> 
> ...



To keep it as simple and generic as possible: When you are limited in how close you can get to your subject, and are using your longest lens, use the sensor with the smallest pixels. 

That's all it really boils down to. It really doesn't matte how big the sensor is, if you can't fill the sensor, then sensor size doesn't matter. When you can't fill the sensor, the best way to extract the most IQ from your setup is to use the camera with the smallest pixels.

I don't think I can make it more layman's than that.


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## HizerKite (Jun 19, 2016)

Sorry to reply to such an old post but just found this online and is very interesting and a great comparison. Last night I took 2 photos of the moon using a 400mm lens + 1.4 x extender. One on my 7D ii and the other on a full frame 1DS mk iii (Old I know). The 7D picture was considerably better - very surprised as images that I haven't cropped so heavily look a lot better on the 1D.

Really interesting to see your direct comparison


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