# 9% larger pixel size on 1D X - how does that translate IQ-wise?



## Redreflex (Oct 18, 2011)

Here's a comparison of relative pixel sizes. Quote from Chuck Westfall (Canon USA Pro Engineering division) via dpreview: (http://www.dpreview.com/articles/5149972341/canon-eos-1d-x-overview)

_When asked to for the biggest improvement in the new camera, Westfall stresses that every aspect of the camera has been re-assessed but finally concludes: 'If you had to highlight just one thing, I'd say the sensor. It's a new level for us in terms of image quality.'

'There's a couple of things that we consider when we think about IQ: number one on this sensor is noise. It's clear the noise level is better than in the 1D Mk IV or the 1DS III. The pixel size is larger than in the 1DS III or 5D Mark II *(6.95 microns, versus 6.4)* and the difference is even more striking compared to the 5.7 micron pixels in the 1D Mark IV. That helps us in terms of light capturing ability and increases the signal to noise ratio. In turn, that does nothing but help the dynamic range of the camera.'_

The pixel size is 8.5% larger in the 1D X compared to 1Ds3 or 5Dm2. 

Everything else being equal, how does that translate into real-world image quality improvement? (I accept there'll be other factors to consider other than pixel size)


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## Gothmoth (Oct 18, 2011)

Redreflex said:


> The pixel size is 8.5% larger in the 1D X compared to 1Ds3 or 5Dm2.



the diameter is 8.5% larger.


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## Edwin Herdman (Oct 18, 2011)

Chuck Westfall demonstrates he isn't an engineer; nothing else. He's a good guy but don't forget he's a PR guy and these numbers might as well have been pulled out of a hat as far as his description of them here.

I accept as true that at some point smaller-size pixels do run into IQ problems. The actual point where you'd draw the line for IQ is not guaranteed to be the point where they are drawing the line, because they have to produce these sensors in bulk and so a smaller pixel pitch could translate into higher reject rates for chips.

I think Gothmoth is right here; this is discussing (as usual) pixel diameter. 9% would be less than a generational change in technology would improve ISO performance, but it fares better than 9% in comparison with the Mark IV (less by far in comparison with the 1Ds Mark III though). I'm not positive my numbers are right, but squaring both micron sizes (1D X versus 1D Mark IV) gives me an end ratio of (1D X micron size / 1D Mark IV size) = 1.486... times the sensor size. You'll note that's a little bit larger than the 1.3x crop factor would allow for (again, I might be making an error here; though it doesn't make sense to normalize one pixel size to the other). It goes to show that, once again, sheer sensor size trumps other considerations, but otherwise this isn't a straight comparison - for a 1.3x sensor camera to compete on a per-pixel basis (remembering that noise or any other picture attribute is meaningless on a single pixel basis) with the 1D X it would have to have a low megapixel count, by any modern standard, which is why I wondered for a moment if it wouldn't make sense to normalize the Mark IV pixels to their size on a full frame sensor (this would be a silly comparison, of course, since they'd be even slightly larger than the 1D X pixels).

My feeling is that Canon is joining Nikon (actually, they did some time ago as a German rep for Canon described a relationship between noise and pixel density which sounded a lot like the typical Nikon statement) in downplaying the importance of more megapixels, but the real calculations on the tradeoffs between ISO and production being done are likely trade secrets and not revealed. Furthermore, many shooters simply are not going to buy this public argument because they require as much resolution as possible. It will be interesting to observe the silence when a 5D Mark II replacement comes out that is also full frame but features a smaller pixel pitch.

The interesting question here, however, is one I would think holds true even if you believe (and I admit it's quite possible) that they actually aren't obfuscating the truth with marketing, and that there is this relationship (and they've only simplified it a bit for the masses) - what are the assumptions about the market use of cameras that leads them to downplay megapixel counts on one camera and not another? The shooting rate of this new 1D X is limited by more than just the number of pixels on the sensor, such as the CPU (in this case, interestingly, we see that the new DIGIC 5 does indeed come in various "flavors," this one being the "5+" but still used in a pair for the new camera, so perhaps a sole 5+ will be the CPU for more mainstream DSLRs, and the "DIGIC 5" may be for compacts, if I have not misread this) and the actual hardware of the SLR mechanisms - in combination, a fast mirror return rate with a high megapixel count sensor would send much more data to the sensor than seen here. If they're using two DIGIC 5+ CPUs, we don't have proof that these CPUs are being taxed to the limit, but it doesn't seem likely that just one would suffice.

9% larger pixels seems less significant to me (and I think the numbers back this up) than just the typical generational change in the sensor production technology and other patented elements that are esoteric and do not follow this easy (and I think misleading) apparent mathematical relationship - like improving microlenses, or most importantly improvements in the photon to signal capture chain (including the ADC).


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## Ivar (Oct 18, 2011)

The only thing needed to be be done for a proper comparison between the technologies (NB! not sensor sizes) is to compare the output for exactly the same sensor area.

Thus, take a high ISO shot (highest native for the 1D mk4 as to stay at the hardware level) with both, with the 1D Mk4 & 1Dx, crop the latter one to the 1.3x (the 1Dx has then 13.85MP left out of 18MP) and downsize the bigger 1D Mk4 file to 13.85MP. This way, it is possible to compare the technologies rather than the cameras. 

The results - the 1Dx might be better per area, but it is not as good as marketing tries to show, it is the sensor size what adds most to the equation, not the individual size of the sensel. 

P.S obviously the real test can be only done when the new X is available.


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## NotABunny (Oct 18, 2011)

Redreflex said:


> Everything else being equal, how does that translate into real-world image quality improvement?



Umm, but nothing else is equal. They are launching a new platform, DIGIC 5: processor and sensor technology.

It's far more interesting to look at the maximum native ISO: 51200. They are confident that this is the maximum native ISO which delivers acceptable quality when a shot must be taken. The maximum native ISO of the 5D2 is 6400, so 3 stops more is mind-bending.


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## mreco99 (Oct 18, 2011)

i guess some actual image output samples will be available very soon, within the next two weeks.


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## Redreflex (Oct 18, 2011)

Edwin Herdman said:


> 9% larger pixels seems less significant to me (and I think the numbers back this up) than just the typical generational change in the sensor production technology and other patented elements that are esoteric and do not follow this easy (and I think misleading) apparent mathematical relationship - like improving microlenses, or most importantly improvements in the photon to signal capture chain (including the ADC).



That seems sensible. It's just interesting that a Canon USA engineer chose pixel size as the one thing to highlight, and not all the other aspects.


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## archangelrichard (Oct 18, 2011)

There is much more to this than just pixel size / count (and that part is often overstated), they have redesigned the microlenses, etc. to improve image quality

the 18 MP is not just about "bigger pixels" but about processing speed - I think that was a target and they had to reduce MP count to keep processing speed at target (note also they have gone from 8 bit to 16bit internally for video processing speed)

I think people need to look beyond the specs to what this accomplishes, what kind of camera this is, where it fits in the marketplace


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## Mark D5 TEAM II (Oct 18, 2011)

Don't expect too much from our main man Chuckie, he's the same guy who said the 50D was two stops better than the 40D at high ISO. :


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## Redreflex (Oct 18, 2011)

Mark D5 TEAM II said:


> Don't expect too much from our main man Chuckie, he's the same guy who said the 50D was two stops better than the 40D at high ISO. :



Ahh... we're only just getting acquainted!


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## Ivar (Oct 18, 2011)

I hope this all stands true.

However, Sony is able to do [email protected] (also on paper like the 1Dx but released in a couple of weeks instead of March). Ok, it will do it at 12bits, but I believe this is the last thing in the chain giving the real tangible differences, what concerns anything over 12bits. 



archangelrichard said:


> There is much more to this than just pixel size / count (and that part is often overstated), they have redesigned the microlenses, etc. to improve image quality
> 
> the 18 MP is not just about "bigger pixels" but about processing speed - I think that was a target and they had to reduce MP count to keep processing speed at target (note also they have gone from 8 bit to 16bit internally for video processing speed)
> 
> I think people need to look beyond the specs to what this accomplishes, what kind of camera this is, where it fits in the marketplace


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## neuroanatomist (Oct 18, 2011)

Redreflex said:


> Edwin Herdman said:
> 
> 
> > 9% larger pixels seems less significant to me (and I think the numbers back this up) than just the typical generational change in the sensor production technology and other patented elements that are esoteric and do not follow this easy (and I think misleading) apparent mathematical relationship - like improving microlenses, or most importantly improvements in the photon to signal capture chain (including the ADC).
> ...



Well, since the _number_ of pixels got smaller, he sure as heck couldn't highlight that, right?


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## Redreflex (Oct 18, 2011)

neuroanatomist said:


> Redreflex said:
> 
> 
> > Edwin Herdman said:
> ...



I think that's the definition of marketing and PR


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## Canon-F1 (Oct 18, 2011)

Gothmoth said:


> Redreflex said:
> 
> 
> > The pixel size is 8.5% larger in the 1D X compared to 1Ds3 or 5Dm2.
> ...



you mean that the pixel AREA has seen a bigger increase then 8.5%?


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## kubelik (Oct 18, 2011)

Ivar said:


> I hope this all stands true.
> 
> However, Sony is able to do [email protected] (also on paper like the 1Dx but released in a couple of weeks instead of March). Ok, it will do it at 12bits, but I believe this is the last thing in the chain giving the real tangible differences, what concerns anything over 12bits.
> 
> ...



Ivar, don't disregard the difference between 12-bit and 14-bit files. I'm still waiting to see 16-bit RAWs on our cameras. the difference, whether perceiving it on-screen or printed, is huge in terms of smooth gradations and color accuracy.


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## Mt Spokane Photography (Oct 18, 2011)

Where do people see 16 bit images in the specs?? I see14 bit images in the specification, and 16 readout channels.

The previous model had 8 readout channels and 14 bits, and Nikon D3S has 12 readout channels and 14 bit images.

I'm not sure that the number of readout channels has much to do with the bit level of the image, I thought it was just pulling data from the sensor in parallel streams data can be read faster.

Doesn't the A/D converter determine the bit depth?

http://www.prophotowiki.com/w/index.php/CMOS

http://news.cnet.com/8301-17938_105-20121138-1/canon-loads-eos-1d-x-with-new-tech-hopes-and-dreams/


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## sjprg (Oct 18, 2011)

:'( Discouraged! Now I have to go back to looking at the Pentax 645D. Canon has the technology but not the will to take on MF.


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## Meh (Oct 19, 2011)

Mt Spokane Photography said:


> Where do people see 16 bit images in the specs?? I see14 bit images in the specification, and 16 readout channels.
> 
> The previous model had 8 readout channels and 14 bits, and Nikon D3S has 12 readout channels and 14 bit images.
> 
> ...



Yes, the press release stated that the 1DX will have a 14-bit ADC and that the new sensor will have 16 channel readout.

Yes, The maximum bit-depth is determined by the ADC. A 14-bit ADC can encode 2^14 (16,384) discrete levels for the voltage at each pixel.


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## Doodah (Oct 19, 2011)

A quick check revealed the 1D3 and 1D4 had 8 channel output

Hopefully the new sensor electronics for the 1DX brings forth improvement in dynamic range, Canon Achille's heel


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## Gothmoth (Oct 19, 2011)

Doodah said:


> hopefully the new sensor electronics for the 1DX brings forth improvement in dynamic range, Canon Achille's heel



Nikon D3S = 8.3 EV

Canon EOS 1D Mark IV = 8.7 EV

Canon EOS 5D Mark II = 8.4 EV

Nikon D3 = 8.6 EV

Nikon D300S = 8.4 EV

all at base iso. 

so not really a overall achilles heel i would say.
if you mean DR in high iso ... well that looks not so good.

ok sony beats them all but .. sony is still no competition in the pro sector.
i rarely have a professionell customer who buys sony.


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## kubelik (Oct 19, 2011)

Mt Spokane Photography said:


> Where do people see 16 bit images in the specs?? I see14 bit images in the specification, and 16 readout channels.
> 
> The previous model had 8 readout channels and 14 bits, and Nikon D3S has 12 readout channels and 14 bit images.
> 
> ...



wasn't saying that the 1D X shot 16-bit. I was saying that I would very much _like_ to see it shoot 16-bit.

Ivar had said there was relatively little difference between 12-bit and 14-bit files, and I was strongly disagreeing with that sentiment, as well as paying a shout-out to a personal wish list item, which is the desire for 16-bit RAW files in the future. hope that clears that one up


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## Meh (Oct 19, 2011)

Doodah said:


> A quick check revealed the 1D3 and 1D4 had 8 channel output
> 
> Hopefully the new sensor electronics for the 1DX brings forth improvement in dynamic range, Canon Achille's heel



I would expect so. Technology has advanced... read noise is down even lower than 1D4 according to press release and in general the chip electronics have shrunk making more room for the photosite in each pixel. Those advances combined with larger pixels should result in more DR. Hopefully it will be close to the recent Sony sensors that are all over 13 stops.


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## Gothmoth (Oct 19, 2011)

kubelik said:


> Ivar had said there was relatively little difference between 12-bit and 14-bit files, and I was strongly disagreeing with that sentiment, as well as paying a shout-out to a personal wish list item, which is the desire for 16-bit RAW files in the future. hope that clears that one up



i hardly see a big difference between 8 bit and 16 bit print on my epson A3 printers (capable of 16 bit printing).
in some cases yes there is a difference.. but overall.. not a big deal.

ok 16 bit makes a big difference if you have computer generated gradients.


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## Gothmoth (Oct 19, 2011)

Meh said:


> Hopefully it will be close to the recent Sony sensors that are all over 13 stops.



source?
the diagram at dpreview is 13 stops overall and i did not see that sony exceeded this diagram..


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## Meh (Oct 19, 2011)

Gothmoth said:


> Doodah said:
> 
> 
> > hopefully the new sensor electronics for the 1DX brings forth improvement in dynamic range, Canon Achille's heel
> ...



Can you point me to where you're getting those numbers from. I've seen higher numbers quoted but possibly none are the definitive source.


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## Meh (Oct 19, 2011)

Gothmoth said:


> Meh said:
> 
> 
> > Hopefully it will be close to the recent Sony sensors that are all over 13 stops.
> ...



Dxomark.com or Sensorgen.info


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## Meh (Oct 19, 2011)

kubelik said:


> Mt Spokane Photography said:
> 
> 
> > Where do people see 16 bit images in the specs?? I see14 bit images in the specification, and 16 readout channels.
> ...



Kubelik, I can't speak for Mt. Spokane, but I did read your comment the way you meant it. The mention of "16-bit" was made in several comments at least one of which I think has been deleted.


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## Meh (Oct 19, 2011)

I must not be thick skinned enough to participate in online forums because I don't like getting smited when I think I'm just politely commenting or responding to other people's posts. Ouch, it hurts. LOL


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## Gothmoth (Oct 19, 2011)

Meh said:


> Dxomark.com or Sensorgen.info



well yes then the canon 1D MK V has over 12 EV too.
but there is a lot of talk what the dxo mark means for real life.

but that going to be OT here.


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## Gothmoth (Oct 19, 2011)

Meh said:


> Can you point me to where you're getting those numbers from. I've seen higher numbers quoted but possibly none are the definitive source.



sorry forgot to give the source... :

they are from dpreview.
numbers as mentioned at base iso.


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## Mt Spokane Photography (Oct 19, 2011)

kubelik said:


> Mt Spokane Photography said:
> 
> 
> > Where do people see 16 bit images in the specs?? I see14 bit images in the specification, and 16 readout channels.
> ...



I wasn't intending to point my comment at you or anyone specific, I saw 16 bit images mentioned in more than one post as well as on other forums, so I just wanted to make sure I was thinking correctly.

I will be quite happy with 18mp, better DR and higher low noise ISO can really open up the possibilities. I struggled with bright light a couple of weeks ago at a local outdoor festival. My 5D MK II could come nowhere near dealing with the huge DR. Even a additional stop would be very welcome.

As far as usable high ISO, two additional stops over my 5D MK II would be a miracle. I feel that ISO 3200 is the highest I can use on the 5D, so usable low noise 12,800 using RAW would be amazing to me and worth the price.

I believe that the extreme high ISO numbers specified (51,200) are for in camera jpeg processing with a ton of NR, which pretty well destroys detail, but does produce a image that is printable, so it is of some limited use.

I expect to order one when pre-orders at Adorama become available.


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## neuroanatomist (Oct 19, 2011)

Gothmoth said:


> Meh said:
> 
> 
> > Can you point me to where you're getting those numbers from. I've seen higher numbers quoted but possibly none are the definitive source.
> ...



Last time looked, DPR's numbers for DR were based on in-camera JPG shots of a step wedge. If that's no longer the case, happy to hear it. If they're still doing that...need I say more?


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## Meh (Oct 19, 2011)

neuroanatomist said:


> Gothmoth said:
> 
> 
> > Meh said:
> ...



That would explain why every camera was measured to have around 8 stops of DR... no matter what the actual dynamic range recorded by the camera they are all converted to the standard jpg file format with 256 levels per colour channel.


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## Edwin Herdman (Oct 19, 2011)

neuroanatomist said:


> Redreflex said:
> 
> 
> > It's just interesting that a Canon USA engineer chose pixel size as the one thing to highlight, and not all the other aspects.
> ...


Why highlight anything at all if it's going to lead people to look for IQ increases in all the wrong places? Even before Canon started toeing this line the amount of people who thought that pixel pitch was the surest way to increase image quality was too much. Within any given camera generation and within a certain sensor size - sure, you're left with not many other options. But that's a big set of assumptions.



sjprg said:


> :'( Discouraged! Now I have to go back to looking at the Pentax 645D. Canon has the technology but not the will to take on MF.


We don't know that yet. Canon's demo 120 megapixel camera had some impressive abilities and it may just be that Canon doesn't want to strain their lens lineup too much - and instead release an actual medium format system or something similar before this so they have lenses that can adequately cope with the new system. Doesn't seem terribly likely, but it's possible. It's also possible they'll change their minds about the idea of a "one-size-fits-all" EOS 1D X, if not in this generation, then in the future.

This doesn't necessarily discount the possibility of an EOS video camera, either (which a number of people were expecting to be announced; instead the video abilities of this camera are merely incremental upgrades to previous models in terms of specification and control, but it will look better if they release some video-specific EF lenses).


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## J. McCabe (Oct 19, 2011)

sjprg said:


> :'( Discouraged! Now I have to go back to looking at the Pentax 645D. Canon has the technology but not the will to take on MF.



Considering past sensor announcements, I think Canon can make a MF camera. I think it's issues with profitability and making new lenses, as higher end equipment sells a lot less than lower end equipment.


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## Canon-F1 (Oct 19, 2011)

neuroanatomist said:


> Last time looked, DPR's numbers for DR were based on in-camera JPG shots of a step wedge. If that's no longer the case, happy to hear it. If they're still doing that...need I say more?



Actually thatÂ´s (imho) closer to reality then the 12-13 Stops from DXO Mark.

8.x EV (9.x with Raw Headroom) seem to be what i can achieve with my 1D MK4.
But i sure come nowhere near the 12 Stops from DXO Mark.



DPreview said:


> Our Dynamic Range measurement system involves shooting a calibrated Stouffer Step Wedge (13 stops total range) which is backlit using a daylight balanced lamp (98 CRI). A single shot of this produces a gray scale wedge from the camera's clipped white point down to black (example below). Each step of the scale is equivalent to 1/3 EV (a third of a stop), we select one step as 'middle gray' (defined as 50% luminance) and measure outwards to define the dynamic range. Hence there are 'two sides' to our results, the amount of shadow range (below middle gray) and the amount of highlight range (above middle gray).







> That would explain why every camera was measured to have around 8 stops of DR... no matter what the actual dynamic range recorded by the camera they are all converted to the standard jpg file format with 256 levels per colour channel.



Sonys Sensor is measured with 9.4 EV.


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## Meh (Oct 19, 2011)

Canon-F1 said:


> neuroanatomist said:
> 
> 
> > Last time looked, DPR's numbers for DR were based on in-camera JPG shots of a step wedge. If that's no longer the case, happy to hear it. If they're still doing that...need I say more?
> ...



I think the point is more about the fact that DPR is using jpeps for the test rather than the fact they're doing a real world visual test by shooting the step wedge and counting the number of stops above and below middle gray before detail is lost. My understanding (and feel free to correct me if I'm wrong) that the jpeg transfer function sacrifices shadow and highlight detail in favor of preserving detail in the middle tones. Something has to be lost to reduce file size and highlight and shadow detail is the least important. The earlier clipping of the shadow and highlights reduces the DR that was captured in the RAW file and this is precisely why by shooting RAW we can pull more detail out of the shadows in post than working with the in-camera jpegs.

When I stated that all the DPR results all came in at 8.x stops I was making the point relative to the numbers in Gothmoth's post (I have not looked for the DRP results for all cameras) and my point was that they were all reduced to about the same level lower than the DxoMark tests. If the Sony sensor was measured 9.4 then perhaps it started with more DR in the RAW file, perhaps the Sony in-camera jpeg applied a less aggressive transfer curve? I don't know, I'm asking because you seem to know about the details of their testing?

Another question I have is, if DPR is shooting the wedge and visually counting the stops what are they viewing it on (monitor, print) and what is the DR of that viewing medium. This I have no clue about so perhaps you know more about that. My understanding though is that modern sensors can record more dynamic range than can be printed and only very high-end expensive monitors can display DR greater than about 10 stops which perhaps DPR was using.

Since you imply you've tested what you can achieve with your 1D4, how did you do your test? Do you have access to a monitor that can display more than 8-9 stops of DR?


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## Gothmoth (Oct 19, 2011)

Meh said:


> . The earlier clipping of the shadow and highlights reduces the DR that was captured in the RAW file and this is precisely why by shooting RAW we can pull more detail out of the shadows in post than working with the in-camera jpegs.



of course.. but you canÂ´t pull 3-4 stops out of a RAW and that is the difference between the two tests.



> My understanding though is that modern sensors can record more dynamic range than can be printed



no question about that.


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## neuroanatomist (Oct 19, 2011)

DPreview said:


> Our Dynamic Range measurement system involves shooting a calibrated Stouffer Step Wedge (13 stops total range) which is backlit using a daylight balanced lamp (98 CRI). A single shot of this produces a gray scale wedge from the camera's clipped white point down to black (example below). Each step of the scale is equivalent to 1/3 EV (a third of a stop), we select one step as 'middle gray' (defined as 50% luminance) and measure outwards to define the dynamic range. Hence there are 'two sides' to our results, the amount of shadow range (below middle gray) and the amount of highlight range (above middle gray).



Yep - JPGs. Actually, for their JPGs, I'm not sure if they use an in-camera conversion or use ACR to convert RAW files. In some reviews they do present an additional analysis of 'RAW headroom' where they push and pull the exposure a bit in ACR (which, I'd argue, is not the best software to use for the 'analysis' since ACR does some 'black box' adjustments).

The other issue is with the statement, "_...from the camera's clipped white point_." They don't say, but I'd assume they determine the clipped white point in the easiest way, by using the histogram and/or highlight warning on the LCD review. Many people claim that they can safely ignore settings like white balance, Picture Style, ALO, etc., because they shoot in RAW, and none of those settings affect the RAW image data, only the metadata. That's technically true, but there's a caveat. When you make an exposure decision based on the histogram on the rear LCD, the luminance data plotted in the histogram aren't derived from the RAW file, they are derived from the JPG preview image generated within the RAW file container (and that image is shown on the rear LCD as well). All those settings that 'dont apply to RAW files' *do* apply to the JPG preview image, and thus to the histogram you are using to assist with your exposure decisions. Thus, since in effect they're using ETTR (for the most transmissive section of the Stouffer wedge), the right side of that histogram might not be far enough to the right.



Canon-F1 said:


> Actually thatÂ´s (imho) closer to reality then the 12-13 Stops from DXO Mark.
> 8.x EV (9.x with Raw Headroom) seem to be what i can achieve with my 1D MK4.
> But i sure come nowhere near the 12 Stops from DXO Mark.





Gothmoth said:


> but you canÂ´t pull 3-4 stops out of a RAW and that is the difference between the two tests.



Despite their flaws, the DPR results are, indeed, closer to real world results. DxOMark's data are accurate, and based on careful empirical testing of the RAW file data, not whatever the camera or ACR do to that data. But the machine-detectable threshold that separates signal from noise is not the same as the human visual system's threshold. I think the DxOMark data are like the EPA estimates of fuel economy on new car stickers and the download speed estimates provided by wireless carriers - useful for relative comparisons of models tested in the same way, but you'll never get those values when you're driving your car or downloading a video.


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## Meh (Oct 19, 2011)

So, after a useful discussion I think we are coming to an understanding/consensus that the DxOMark tests are representative of the DR the sensor is actually capable of and the DPR tests are an attempt to test what DR we can expect in final images but may be coming in low by somewhere in the range of 1-2 stops due to testing limitations, in particular the use of jpegs that by definition lose some detail in the shadows and highlights. And perhaps the rest of the difference is due to say another half stop on either end (shadows and highlights) that the sensor can detect but can't be seen anyway.

The original comment that started this conversation was that DR has been Canon's Achilles heal. In both sets of measurements it would seem that they are in fact behind by about a half to a full stop of DR when comparing sensors from the same point in time and that is most likely due to Canon's emphasis on higher resolution. The 1DX will likely change that though.

Does that sound about right?


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