# 7dII FOCUSING PROBLEMS WITH 300MM PRIME LENS



## BobAaron (Feb 26, 2015)

I have both the 7D and the 7dii. I had the 7D for nearly a year and the 7Dii was supposed to be an upgrade for me.
Both cameras were set to the same exact settings (or as close as possible given that the shutter speeds have slight variations, etc.). I was shooting horse races using both the 70-200mm f/2.8 L IS II and the 3oomm f/2.8 L IS prime lens. On day one I used the 7D and 7Dii with the 70-200 lens alternating cameras one race after the other. On day two I alternated cameras race by race using the 300mm. RESULTS: Both the 7D and 7Dii shot identical quality shots using the 70-200mm. Using the 300mm prime lens, only the 7D shot in-focus shots one after the other. Nearly every shot taken by the 7dii was blurry. I spent a solid week testing and retesting. Same results.

There is something inherently wrong with here. Compatibility issues? Maybe? I sent the 7Dii back to B+H which honored their 30-day return policy.

Now my search for an upgrade to the 7D continues. I thought the 7Dii would be that upgrade but it turned out to be a huge disappointment!


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## Invertalon (Feb 26, 2015)

I will ask the obvious question... Did you microadjust the lens properly to the body?

If not, go do that first and then see how they compare. The lens may not need any adjustment on the 7D but may on the 7D2. Each body is different.


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## FEBS (Feb 26, 2015)

Invertalon said:


> I will ask the obvious question... Did you microadjust the lens properly to the body?
> 
> If not, go do that first and then see how they compare. The lens may not need any adjustment on the 7D but may on the 7D2. Each body is different.



+1
I have both 7d And 7d2. I don't get the results as OP mentioned. For me the 70-200 II And the 300 II are doing great job on both cameras


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## NancyP (Feb 26, 2015)

Correctable firmware issue in 7D2? 
OP uses 300 f/2.8L IS I, FEBS uses 300 f/2.8L IS II.


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## FEBS (Feb 27, 2015)

NancyP said:


> Correctable firmware issue in 7D2?
> OP uses 300 f/2.8L IS I, FEBS uses 300 f/2.8L IS II.



I know the versions of the 300 are different between mine and OP. However, I did not hear if the OP has AFMA his lens. 300mm on a crop means 480mm, that implies that the AF should be really top notch, so AFMA is really needed. I think he needed to do that to see if there really was a problem before sending the 7D2 back.


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## privatebydesign (Feb 27, 2015)

FEBS said:


> NancyP said:
> 
> 
> > Correctable firmware issue in 7D2?
> ...



No it doesn't! It means 300mm, because that is what a 300mm lens is, it is a 300mm lens, stop with the crop crap.


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## FEBS (Feb 27, 2015)

privatebydesign said:


> FEBS said:
> 
> 
> > NancyP said:
> ...



You are right that a 300m stays a 300mm on a crop looking at the point of compression of your picture. however, the dof is smaller on a crop compared to a FF. The 300mm on a crop at 6m, f/2.8 gives a dof of 40.8mm and on a FF it is 64.5mm. So for that reason AFMA is even more needed on a crop compared to a FF when working with long lenses.

Why is crop crap ? You don't like the crop cameras? I prefer mostly the photos of my FF, however, in certain cases, I'm happy to have a crop as the reach of the lenses will be increased. I fully agree that it is not a factor 1.6 as cropping on a 5D3 is really good. The 1Dx doesn't give me the same possibilities due to the smaller Mp (18 vs 23). But the 7D2 has sure advantages. The mp compared to the 5D3 (20 vs 23) is much smaller, and has a good AF, better then 7D before, comparable to 5D3. So when the light is good, my 7D2 can really give me more mp on a distant object compared to the 5D3 or 1Dx. The compression of the photo stays of course the same for crop or FF.


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## AlanF (Feb 27, 2015)

He is not saying crop is crap, he is saying that the statement that a 300mm lens is a 480 mm lens on a crop is crap.


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## AlanF (Feb 27, 2015)

The OP posted in another thread http://www.canonrumors.com/forum/index.php?action=profile;area=showposts;u=375238 

"What does AFMA mean??? "

People join the forum to learn, so it is great that he has asked. But, it's somewhat tough on B&H when people buy a camera from them and return it because they haven't read the manual.


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## FEBS (Feb 27, 2015)

AlanF said:


> The OP posted in another thread http://www.canonrumors.com/forum/index.php?action=profile;area=showposts;u=375238
> 
> "What does AFMA mean??? "
> 
> People join the forum to learn, so it is great that he has asked. But, it's somewhat tough on B&H when people buy a camera from them and return it because they haven't read the manual.



Thanks for that info. 

Indeed reading a manual seems to be very difficult. I must say, that nowadays before I buy a new camera I do already read the manual in advance, to know what I will be getting. However when I bought the 7D a few years ago, I took me about a year to understand and remember everything thereabout. I look regular on this forum for things like AFMA and other things. I really don't know why people buy a 7D or even more advanced, and then use only automatic programs or all focuspoints, and then start complaining about the device. Really strange. To me, it seems that several people do buy high end devices (and even not only cameras) just to show they have the latest, or more advanced, or... but they never try to use all the possibilities of the device. Just a shame to spend that much money.

About a 300mm on FF or 480mm on crop, indeed a 300mm stays a 300mm from way of compression of the picture. However when I look to the pixels covered by an object then the 300mm on a crop will give the same result as a 480mm on a FF. Not on a base of compression, but only on pixels on the subject. Also the dof will be much smaller on the crop compared to a FF, with the same lens. For that reason, AFMA for a 300mm on a crop is very important.


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## privatebydesign (Feb 27, 2015)

FEBS said:


> AlanF said:
> 
> 
> > The OP posted in another thread http://www.canonrumors.com/forum/index.php?action=profile;area=showposts;u=375238
> ...



As AlanF pointed out, I wasn't, and never have, denigrated crop cameras, indeed I own one. But people, even now, seem strangely uncomprehending of what they actually do, I am sure in large part to the initial sales push by marketing departments and then continued lack of real education for the majority of buyers who, in truth, probably don't actually care too much. 

I also agree with AlanF on how tough this purchasing of complex equipment is on retailers when purchasers won't even read the manual. Though manuals have taken a strange persona of their own nowadays, computers come without one and my hotshoe flash manual is several hundred pages! But declaring issues and problems without a fairly good understanding of the problem is the new way of life it seems. That is cool, it means there is even more work for those that can deliver........

As for 300mm and crop camera dof, as always, a little knowledge is a dangerous thing.

In all three following scenarios assume the same exposure information for both users.

So, two people standing next to each other both with brand new 300mm f2.8 IS MkII's, one with a 7D mkII the other with a 5D MkIII. They sit in a hide together and across a field there is a fence, a bird lands on the fence, the crop camera owner has tighter framing but still needs a small crop, the ff owner needs to crop much more to get the same framing but so what, it is a nice shot. Who has less dof? Neither, dof in both images is identical.

Same scenario but both guys decide their wider shot is actually a nice environmental shot that shows the birds habitat well and the light is just catching the fence nicely, obviously the ff camera shows more fov view but both images work well, so, same place, same lens, same aperture, different sized sensors and therefore different framing, who has less dof? The crop camera. Why? Not because it is a crop camera (or because he is using a mythical 480mm lens), but because the captured data is enlarged more, the bigger you make something the less sharp it is, dof is about apparent sharpness so the more you enlarge something the less dof it has.

Same scenario, the bird flies to a second fence much closer to the hide. The ff user can still use his 300 for a frame filling shot of the bird, the crop camera user has to swap out his 300 to a 70-200 to get the same framing, he zooms to about 190mm to get the same framing as the ff user and they both take the same framed shot from the same place with the same camera settings, just different focal length. Who has less dof? The ff user, at the same distance a 300mm at any aperture will give you less dof that a 190 at that same aperture, this difference will be greater than the difference between the enlargement amounts.

So depending on the specific scenario the dof of a crop camera can be shown to be the same as, or narrower, or deeper, than a ff camera. 

Further, "compression" is a very bad way of expressing perspective. Compression is dependent on where you are in relation to your subject, nothing else, the lens does not create "compression". In the three scenarios above who has the most compression in each situation? Neither, they are both shot from the same place in relation to the subject so all the images have the same perspective. That means the "compression" is the same in all those above situations.


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## bholliman (Feb 28, 2015)

privatebydesign said:


> In all three following scenarios assume the same exposure information for both users.
> 
> So, two people standing next to each other both with brand new 300mm f2.8 IS MkII's, one with a 7D mkII the other with a 5D MkIII. They sit in a hide together and across a field there is a fence, a bird lands on the fence, the crop camera owner has tighter framing but still needs a small crop, the ff owner needs to crop much more to get the same framing but so what, it is a nice shot. Who has less dof? Neither, dof in both images is identical.
> 
> ...



Excellent illustration! I still struggle to understand these concepts at times, this helps.


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## NNature (Apr 5, 2015)

Perspective is also a word that is (mis)used in these discussions, when Field Of View is the more correct one.

The depth of field is quite simple to understand.
If you have the same focal length, aperture and distance to the "object" you are photographing, it doesn't matter if you have a FF or crop camera. The depth of field will be the same.

Some people think that if they change the camera to a FF camera from a crop camera they will get shallower depth of field, which is not true (with the same FL, f and distance).


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## East Wind Photography (Apr 5, 2015)

My perspective is that AFMA is important whether you own a full frame or crop sensor camera. How is that for compression?


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## Lee Jay (Apr 5, 2015)

NNature said:


> The depth of field is quite simple to understand.
> If you have the same focal length, aperture and distance to the "object" you are photographing, it doesn't matter if you have a FF or crop camera. The depth of field will be the same.
> 
> Some people think that if they change the camera to a FF camera from a crop camera they will get shallower depth of field, which is not true (with the same FL, f and distance).



If it's so simple, how come you got that wrong?

http://dofmaster.com/dofjs.html

7D, 100mm, f/2.8, 10 feet, DOF = 0.32 feet
5D, 100mm, f/2.8, 10 feet, DOF = 0.50 feet


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## neuroanatomist (Apr 5, 2015)

Lee Jay said:


> NNature said:
> 
> 
> > The depth of field is quite simple to understand.
> ...



Like many, he's apparently trapped within the circle of confusion.


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## monkey44 (Apr 5, 2015)

Ah soooo, grand master, seems to be missing the magical 1.6 crop factor calculation we mis-use so often.


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## AlanF (Apr 5, 2015)

Lee Jay said:


> NNature said:
> 
> 
> > The depth of field is quite simple to understand.
> ...



Maybe what he/she means is that if you cropped the 5D image to be the same as the 7D, then that crop would have the same dof as the full image on the 7D?


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## NNature (Apr 11, 2015)

Yes it was kind of sloppy to say "when everything is equal" and not mention framing. In real life you want the same framing no matter what sensor size you use, but I should have included that info as well and not take for granted that everyone would understand that.
I just agreed with privatebydesign in his first example of the bird shot where he say that DoF is the same, when everything is equal (incl. framing!!!)
If you consider that you want the framing to be the same, you have to use the same CoC in those tables someone linked to.

As always, the best thing to do is to grab your gear and go out and take some pictures instead of looking at tables on internet. 
That's what I will do now if I can get out of this circle of confusion... ;D


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## dslrdummy (Apr 11, 2015)

Just shows that if you're going to make emphatic statements, make sure you get it right.


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## East Wind Photography (Apr 11, 2015)

dslrdummy said:


> Just shows that if you're going to make emphatic statements, make sure you get it right.



No you don't have to get it right. You just need to accept the gauntlet of experts (both photographers and linguists) that will ensue on CR to attempt to belittle you into leaving. 

It's ok to mis-speak as long as someone else clarifies to make it right. After all, that is why we are here, To get answers to questions and concepts that are not always fully and accurately understood.


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## Lee Jay (Apr 11, 2015)

NNature said:


> Yes it was kind of sloppy to say "when everything is equal" and not mention framing. In real life you want the same framing no matter what sensor size you use, but I should have included that info as well and not take for granted that everyone would understand that.



The reason we didn't understand that is that you said the opposite. You said, "If you have the same focal length, aperture and distance to the "object" you are photographing...". If those are all the case, you _don't_ have the same framing. Regardless, it's wrong anyway.

Let's say you adjust one of your constants so that you do have the same framing. Let's use the logical one and adjust focal length by the crop factor.

100mm * 1.6 = 160mm.

7D, 100mm, f/2.8, 10 feet, DOF = 0.32 feet
5D, 160mm, f/2.8, 10 feet, DOF = 0.19 feet

Oops...not the same even with the same framing.

If you want DOF to be the same across formats, and you want to hold framing constant, have have to multiply _both_ focal length _and_ f-stop by the crop factor.

f/2.8 * 1.6 = f/4.5

7D, 100mm, f/2.8, 10 feet, DOF = 0.32 feet
5D, 160mm, f/4.5, 10 feet, DOF = 0.30 feet (the difference is caused by round-off error).


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## serendipidy (Apr 11, 2015)

This is all so circle of confusing to many, including me. But I remember some people on this site have boiled it down to:
DOF depends only on true aperature size and image magnification (or something to that effect). Is that correct?


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## Ruined (Apr 11, 2015)

BobAaron said:


> I have both the 7D and the 7dii. I had the 7D for nearly a year and the 7Dii was supposed to be an upgrade for me.
> Both cameras were set to the same exact settings (or as close as possible given that the shutter speeds have slight variations, etc.). I was shooting horse races using both the 70-200mm f/2.8 L IS II and the 3oomm f/2.8 L IS prime lens. On day one I used the 7D and 7Dii with the 70-200 lens alternating cameras one race after the other. On day two I alternated cameras race by race using the 300mm. RESULTS: Both the 7D and 7Dii shot identical quality shots using the 70-200mm. Using the 300mm prime lens, only the 7D shot in-focus shots one after the other. Nearly every shot taken by the 7dii was blurry. I spent a solid week testing and retesting. Same results.
> 
> There is something inherently wrong with here. Compatibility issues? Maybe? I sent the 7Dii back to B+H which honored their 30-day return policy.
> ...



Regardless of all the unrelated banter in this thread, I do believe a larger than usual number of 7D2 bodies were released with major autofocus problems. There are too many postings like this across many forums and Canon is replacing hardware in many cases to fix it or making hardware adjustments.


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