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80D vs 7D Autofocus - practical examples - comments welcomed (1 Viewer)

Shumi

Active member
Hi All, I would be very grateful for your comments on the following.

I was choosing between Canon 80D and 7D Mark 2 last year – and eventually opted for 80D based on a combination of factors. I do plan to use my camera mostly for shooting birds – and I understood from the beginning that 7D has got a better autofocus, but did not think that the difference would be very significant (esp with still birds that i shoot most). Now I am starting to wonder whether I might have underestimated the difference :)

Attached are two pictures that I took last weekend in a remote nature reserve in northern Ukraine. I used the Canon 100-400 II lens.

On one picture is a male black grouse displaying on a lek at dawn – distance 200 meters, very early in the morning. F 7.1, ISO 400, 1/500, 400 mm, handheld. As you may see, the grouse is hopelessly out of focus – and this is the situation with 95% of pictures of that grouse that I took that morning. I am now thinking whether the superior autofocus function at 7D could have prevented this?

On the second picture is a Tengmalm’s owl, pictured at night at the distance of 10 meters under a flashlight. I did not use an external flash (do not think it is good to use it on owls anyway). F 5.6, ISO 6400, 1/40, 400 mm, handheld. The picture is not particularly sharp. The question I have is about the reason for this lack in sharpness – is it because the lighting conditions were poor, hence only 1/40 shutter speed and hence the blurring, or was it because the 80D autofocus failed to focus properly in poor lighting conditions? If the latter, could 7D have prevented that?

I would be extremely grateful for your views on the above.

Thank you
 

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marcsantacurz

Well-known member
I cannot answer your whole question, but 1/40th handheld at 400mm is pushing it. Canon claims 4 stops of IS, so that would be about 1/640th compensated. Your equivalent focal length is 640mm on 80d (assuming you did not crop). So you have exactly 1/focal_length shutter speed, which is usually considered the minimum you want. So it could just be the shutter speed is too low. If you cropped, then you were probably too slow especially handheld.

On my Nikon, for the auto ISO setting, I select a "faster" minimum shutter speed so it will use more like a 1/1.5*focal_length rule. I'm not sure if there's an equivalent setting for Canon or if you were even using an automatically selected shutter speed.

Also, at 10m, a 400mm lens at f/5.6 on a 1.6 crop sensor has a depth of field of only +/- 0.06m (~2.3"), so you might also be getting some DoF blur. It's probably borderline at 10m. The closer you get, the shallower the DoF will be.

For the grouse, it does look like the camera picked up the background clutter more than the bird. I know this is a problem with a lot of autofocus systems. Were you using a single point or small group autofocus? I find those help me most of the time.
 

Shumi

Active member
Thanks so much marcsantacurz for your reply.

I was using single point autofocus for both pictures. I always tend to use single point if I am shooting a still single bird. Is that also the approach you take?
 

marcsantacurz

Well-known member
Thanks so much marcsantacurz for your reply.

I was using single point autofocus for both pictures. I always tend to use single point if I am shooting a still single bird. Is that also the approach you take?

On Nikon, I usually use 3d tracking mode, which is a single small focus point that will track when shutter half depressed. Sometimes I use the "group AF" mode where it uses 5 points in a cross to track. I usually find the area AF modes pick the wrong things, and if I do use them I use the smallest two sizes.

For the grouse, it's a small black blob that is probably hard for the AF to lock on to, especially if it's small compared to the size of an AF point. I've not used the 80d or 7dm2, so I cannot say if the 7d would do better.

Marc
 

Shumi

Active member
Thank you, Marc, for your helpful comments!

If any users of 7D Mark ii could also comment on their experience with autofocus, I would be very grateful.
 

stevo

Well-known member
I have both cameras,the 7dmkii has a much better af system for tracking birds.I suspect possible heat haze though on your black grouse shot.
 

Shumi

Active member
Thanks, Stevo. Does 7Dmkii autofocus work better for tracking moving birds, or does it do a better job at capturing/focusing on still birds as well? If we take that black grouse example and the possible hear haze problem, could 7dmkii have prevented that?
 

njlarsen

Gallery Moderator
Opus Editor
Supporter
Barbados
Not used any of the cameras mentioned, but I have noticed other cameras having problems with black birds that take up small parts of the view finder. Given the way the background looks, heat haze is not the entire explanation.

Regarding the owl: you are meaning a flashlight in the sense of a torch not in the sense of the build in flash? Under those conditions I think the long shutter is the main culprit. Under such conditions I have in the past experienced that series of 2-3 images per time I press the shutter and repeating many times gives improved chances that one of the images hit that magic of best AF and best holding still of the camera with best stillness of the bird. I have not tried your camera so something might change the equation when using that.

Niels
 

stevo

Well-known member
Thanks, Stevo. Does 7Dmkii autofocus work better for tracking moving birds, or does it do a better job at capturing/focusing on still birds as well? If we take that black grouse example and the possible hear haze problem, could 7dmkii have prevented that?




Yes to your first question,no to your 2nd question.No camera can really deal with atmospheric heat haze.
 

Gronk08

Well-known member
With the Grouse shot I think the distance is playing a big part, at that range any heat haze will be magnified and at that distance picking out the bird from the background will be very tricky for the AF to fully lock on to the subject.
I have the 750D with the Tamron 150-600 G1 and found it to be a good combo but I will say I wouldn't try getting more than a record shot at that sort of distance.
At 200m you are probably into the realms of needing a 600mm f4 and TC's to get a reasonable shot.

Tim.
 

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