D7500 vs D500 - autofocus

[DaveyDitzer]

I currently use D7500 with 200-500mm for bird photography. After upgrading from D5600 (less than a year ago) I'm very satisfied with the speed, buffer, ergonomics and low light performance.

However there's one aspect I ocassionally complain about - I get considerable number of images with focus plane landing slightly behind or in front of bird's eye (mostly behind), even when I keep the focus point on the eye in the viewfinder (single point mode). It was more or less the same with D5600 which has 39 AF points instead of 51.

I don't think it's the problem with AF fine tuning though, the results are too inconsistent for that. Sometimes focus lands perfectly fine and ocassionally I get some front focus too.

So now I'm wondering, is AF in D500 a significant step up in this regard? Obviously Z8 would be the best answer to this problem, but it's nowhere near my budget.

Or maybe I'm looking at this completely wrong and the problem lies a few inches behind the viewfinder?

Any insights appreciated!

EDIT: One more thing to mention, probably quite important: I'm using AF-C with back button focus. I usually keep the back button pressed when keeping the AF point on the eye.

View attachment 80535

View attachment 80537

If you keep the BBF pressed and move the camera, is it possible that the focus system is picking up something other than the eye?

 

[txstone]

I tested the autofocus of the D500, D5, and D850 with battery grip and EN-EL18 battery, with the same lens and photographing osprey leaving and returning to their nest. The D5 was considerably better at tracking and focusing on the birds as they rapidly approached the camera. My hit rate was 100% with the D5 and less than 10% with the D850 and D500.

I believe the D5 and D500 have the same 153 point AF. If they use the same AF, why would the D5 give you a (much) higher hit rate?

I've used the D7500 and D500 a lot with BIF and never been in a situation with a 10% hit rate. Except maybe trying to get those barn swallows in flight catching bugs ...With a known to/from location (like an Osprey nest) I'd expect a very high hit rate with any of these cameras. Especially with larger birds like the Osprey.

Though the D7500 versus D500 comparison might be interesting to debate, I've never heard of anybody that didn't think the D500 had an absolutely top of the line AF.

Note that Carlson says the D5 was better at 'tracking and focusing..' 'on the birds as they rapidly approached the camera'.

If you look for comparison of the D5, D850 and D500 AF Systems, yes they have the same basic AF systems with dedicated AF processors (I didnt look up to see if these are the same processor not), but performance still varies, especially around tracking, e.g.,

Not quite as good? Nikon D850 versus Nikon D5 subject tracking

Photographer Matt Granger recently pitted the Nikon D850 up against the flagship D5 in a subject tracking battle royal, proclaiming the D5 comes out on top. Is he right? Here's our take

www.dpreview.com

Setting new standards: Nikon D5 Review

The Nikon D5 is the newest iteration of the company's action-oriented flagship DSLR. Its headline features include a new Nikon-developed 20.8MP full-frame sensor and 153-point AF system. More than anything, though, the D5 is a camera designed to just work - no matter what conditions you're in...

www.dpreview.com

 

[PhotoLover]

Note that Carlson says the D5 was better at 'tracking and focusing..' 'on the birds as they rapidly approached the camera'.

If you look for comparison of the D5, D850 and D500 AF Systems, yes they have the same basic AF systems with dedicated AF processors (I didnt look up to see if these are the same processor not), but performance still varies, especially around tracking, e.g.,

Not quite as good? Nikon D850 versus Nikon D5 subject tracking

Photographer Matt Granger recently pitted the Nikon D850 up against the flagship D5 in a subject tracking battle royal, proclaiming the D5 comes out on top. Is he right? Here's our take

www.dpreview.com

Setting new standards: Nikon D5 Review

The Nikon D5 is the newest iteration of the company's action-oriented flagship DSLR. Its headline features include a new Nikon-developed 20.8MP full-frame sensor and 153-point AF system. More than anything, though, the D5 is a camera designed to just work - no matter what conditions you're in...

www.dpreview.com

First I'll note that the OP has gone away and apparently not found any of our comments useful. So perhaps we should all just stop typing in this thread

Second I'll have to say that my experience with the D7500 (and later the D500) mirrors that of woodyg3; I'm quite certain I've never had a hit rate as low as 10% on birds as large as Ospreys. They can be hard to track when they start their dive to hit a fish if you are close (trying to fill that frame!) because sometimes they will drop like a stone, other times take a more shallow route. And they may or may not give a clue they are about to dive. But hovering, flying to and from a nest, coming out of the water and so forth generally they are not moving extremely fast. Usually group AF will lock on them quite well. Unless there was something very difficult about the setting (really complicated close background, which would be odd for a nest??), I'd think getting Ospreys going to/from a nest would be straightforward. But perhaps I'm missing something (still ... 9x the hit rate over a D500 using the D5??).

But the D5/D500 thing is sort of a tangent; the question was about the D7500/D500 class cameras I thought. And I think both those crop-sensor cameras have very good to outstanding AF, suitable for demanding to very demanding wildlife shooting. At least I've found their AF good, and while I think I'm decent at tracking moving subjects, I don't think I'm especially talented at it. When I have a miss, it is almost always my fault (I can see the AF point slip off starting a burst, or in review the camera is showing me the AF point is not on the subject, etc).

 

[Fenrir]

One more question I forgot to ask, when you get misses on the AF with single point, are you using the center focus points, or have you selected some of the outer ones to get a different composition? When you move away from the center, you lose some/all of the cross sensors and AF speed and accuracy is decreased. This is one place where the D500 should definitely be better than the D7500, though unless you have an F/4 or faster lens, some of those points are not used.

I'm sorry for replying late.

When using D7500 I always try to go for one of the nine points in the middle of the AF area. The are some cases I find it's necessary to go for one of the outer points (non-cross type ones) in order to frame properly. In those scenarios I just do it and hope for the best. Although these are rather few and far between and in the snapshots I showed you in the original post the subject was almost in the middle of the frame.

The fastest aperture I'm using for birds is f/5.6.

I believe the D5 and D500 have the same 153 point AF. If they use the same AF, why would the D5 give you a (much) higher hit rate?

I suspect the pixel density may play some role in this. D5 is more forgiving when it comes to sharpness issues (probably not enough for 90% KR difference though).

 

[Fenrir]

2. Set the focus point to the center and lock it there. Using BBF you can focus, release the button and recompose.. Birds are twitchy and can move an inch or two in the time it takes to do this, though. This also helped me.

Birds moving is one thing, but what makes me skeptical about this technique is that the photographer's movement can take the subject slightly out of the focus plane. Nevertheless I'm gonna do some experiments with it, because I almost exclusively use a non-center point for non-center subjects.

 

[PhotoLover]

I'm sorry for replying late.

When using D7500 I always try to go for one of the nine points in the middle of the AF area. The are some cases I find it's necessary to go for one of the outer points (non-cross type ones) in order to frame properly. In those scenarios I just do it and hope for the best. Although these are rather few and far between and in the snapshots I showed you in the original post the subject was almost in the middle of the frame.

The fastest aperture I'm using for birds is f/5.6.


I suspect the pixel density may play some role in this. D5 is more forgiving when it comes to sharpness issues (probably not enough for 90% KR difference though).

There is no doubt that unless the contrast is good and the light strong, those off center focus points will sometimes struggle to get lock. I see that with both the D7500 and the D500. I imagine the D500 would do better, except alas the lens I use for birds are all 5.6 or smaller aperture lenses, which means the outside cross sensors won't get used on the D500. I use the non-center points at times, but they are more likely to disappoint. And as I mentioned, sometimes movement on my part or the critter's part result in the point slipping off where I want.

 

[Fenrir]

There is no doubt that unless the contrast is good and the light strong, those off center focus points will sometimes struggle to get lock. I see that with both the D7500 and the D500. I imagine the D500 would do better, except alas the lens I use for birds are all 5.6 or smaller aperture lenses, which means the outside cross sensors won't get used on the D500. I use the non-center points at times, but they are more likely to disappoint. And as I mentioned, sometimes movement on my part or the critter's part result in the point slipping off where I want.

It's actually good to know that D500 loses the lateral cross-type points with f/5.6 optic. So it basically has 45 cross-type points instead of 99. This will probably contribute to my decision on whether to replace D7500 with this camera or to spend my $$$ on something else e.g. 500 PF. That's because I don't plan to go for a faster glass (at least for now), mostly due to its cost and weight.

Speaking of 500 PF, if I recall correctly you used it with D7500, right? Were you able to program the function button on this body?

 

[PhotoLover]

It's actually good to know that D500 loses the lateral cross-type points with f/5.6 optic. So it basically has 45 cross-type points instead of 99. This will probably contribute to my decision on whether to replace D7500 with this camera or to spend my $$$ on something else e.g. 500 PF. That's because I don't plan to go for a faster glass (at least for now), mostly due to its cost and weight.

Speaking of 500 PF, if I recall correctly you used it with D7500, right? Were you able to program the function button on this body?

Yeah, unless the lens is f/4 or faster you don't get the full advantage of the outside cross sensors. The earlier thread I linked to had some discussion on this point and referenced the Nikon documentation pointing this out.

I have the function button on the 500 pf set to go to a preset focus area; I don't *think* you can have it do anything else on the D7500 but would have to check. I do like having a button on the D500 body set to go to single point AF. On the other hand, I cordially detest the D500 banks. The D7500 U1 and U2 are quick and easy to use.

I rented the 200-500 for a week. If I had to choose between a 200-500 on a D500 or a 500 pf on a D7500 I'd go with the latter combo every time -- for birding. Obviously the 500 pf being a prime is less versatile. But it's super sharp, fast AF, and light to carry and use. You can lug that thing around all day. By contrast I found the 200-500 was about as heavy (well, heavier) than I'd like to carry for an extended time. You can also pick up a 500 pf cheaper now (though still more expensive than a D500 used body). But then you have to decide, well, when do I want to spring for the Z8 or Z9 .....

I did experiment a bit with the D500 today using my 70-200 2.8 and a 1.4 converter (so a 4.0 lens). I was playing around, practicing BIF with some Bonaparte gulls. My completely unscientific opinion is that I could move the focus area (group AF) all the way to the sides and it could still lock on fairly well. Better than with my other lens. But I didn't have the D7500 body to compare with me and I almost never try the focus area that far over on BIF when I really care about getting the picture.

 

[Fenrir]

I rented the 200-500 for a week. If I had to choose between a 200-500 on a D500 or a 500 pf on a D7500 I'd go with the latter combo every time -- for birding. Obviously the 500 pf being a prime is less versatile. But it's super sharp, fast AF, and light to carry and use. You can lug that thing around all day. By contrast I found the 200-500 was about as heavy (well, heavier) than I'd like to carry for an extended time. You can also pick up a 500 pf cheaper now (though still more expensive than a D500 used body). But then you have to decide, well, when do I want to spring for the Z8 or Z9 .....

Z8 is definitely on my radar since its release, but will probably stay out of the budget for quite a while.

200-500 is my only wildlife lens now and a pain to carry around, even for a few hours.

Did you try to use D7500 and 500 PF on the shutter speed 1/200s or slower? VR systems in the earliest PF lenses are known to suffer from the mirror slap in some circumstances. I know my 300 PF did (on D7500) and it's one of the main reasons I don't own it anymore. The ability to do longer exposures is important to me, especially when I'm trying to photograph perched birds in some ugly winter overcast.

VR in 200-500 is excellent. Very hard to match.

 

[PhotoLover]

Z8 is definitely on my radar since its release, but will probably stay out of the budget for quite a while.

200-500 is my only wildlife lens now and a pain to carry around, even for a few hours.

Did you try to use D7500 and 500 PF on the shutter speed 1/200s or slower? VR systems in the earliest PF lenses are known to suffer from the mirror slap in some circumstances. I know my 300 PF did (on D7500) and it's one of the main reasons I don't own it anymore. The ability to do longer exposures is important to me, especially when I'm trying to photograph perched birds in some ugly winter overcast.

500 pf is decent at lower shutter speeds. I will go down to 320 or 250 for stationary targets in low light handheld (prefer more but ...). I checked one large set of shots and while using 320 was not that uncommon, 250 is rare and 125 somewhat unique for that lens in my hands. I took a picture I like of a perched green heron at 125

(https://bcgforums.com/posts/349518/?simple_view=1, third one down).

As I rarely work off a tripod, I don't get down that low very often, I mean, VR or not it is a 500 lens, 750 FF equivalent which is 15x magnification. My recollection of the green heron shot (I was doing the Steve recommendation of dropping shutter speed in increments to try and get the lowest ISO possible) was that I was getting fairly sharp images and I just picked the one I liked the best at the slow speeds/lower ISO. I was in burst mode, but I'm pretty much always in burst mode. I try to be at 400 or above for perched critters. It's nice that you can leave the thing in sport VR mode at about any shutter speed. If I had to shoot more at low shutter speeds I would rely upon burst mode partly for success.

For image quality + usability (easy to carry, good AF, good VR etc) the 500 pf is a fantastic lens. But it's not an f/4 lens and sometimes when it is dark ...

 

[Fenrir]

500 pf is decent at lower shutter speeds. I will go down to 320 or 250 for stationary targets in low light handheld (prefer more but ...). I checked one large set of shots and while using 320 was not that uncommon, 250 is rare and 125 somewhat unique for that lens in my hands. I took a picture I like of a perched green heron at 125

(https://bcgforums.com/posts/349518/?simple_view=1, third one down).

As I rarely work off a tripod, I don't get down that low very often, I mean, VR or not it is a 500 lens, 750 FF equivalent which is 15x magnification. My recollection of the green heron shot (I was doing the Steve recommendation of dropping shutter speed in increments to try and get the lowest ISO possible) was that I was getting fairly sharp images and I just picked the one I liked the best at the slow speeds/lower ISO. I was in burst mode, but I'm pretty much always in burst mode. I try to be at 400 or above for perched critters. It's nice that you can leave the thing in sport VR mode at about any shutter speed. If I had to shoot more at low shutter speeds I would rely upon burst mode partly for success.

For image quality + usability (easy to carry, good AF, good VR etc) the 500 pf is a fantastic lens. But it's not an f/4 lens and sometimes when it is dark ...

I see. Thank you for the insight. This green heron picture is of a great quality, at least at that crop. Gives me hope for using this combination in low light

And yeah, in those scenarios you basically "spray and pray" - that goes without saying. I must say I find it oddly satisfying when I take 10 photos at a very low shutter speed and one of the pictures is tack sharp!

Truth be told, I don't go for 1/125s handheld. I think the lowest I went with 200-500mm was around 1/250s when I was sitting down and supporting the lens barrel on my knee. But I did try to photograph some predictable Paridae birds this winter using a monopod. Shutter speeds 1/125s-1/160s were the norm during this session and the photos came out quite sharp and clean. That's why the VR efficiency in this range matters to me.

Here's some unprocessed example at 450mm 1/125s f/7.1 ISO-2200, moderate crop.
(zooming out was accidental, I didn't notice I moved the barrel )

 

[PhotoLover]

I see. Thank you for the insight. This green heron picture is of a great quality, at least at that crop. Gives me hope for using this combination in low light

And yeah, in those scenarios you basically "spray and pray" - that goes without saying. I must say I find it oddly satisfying when I take 10 photos at a very low shutter speed and one of the pictures is tack sharp!

Truth be told, I don't go for 1/125s handheld. I think the lowest I went with 200-500mm was around 1/250s when I was sitting down and supporting the lens barrel on my knee. But I did try to photograph some predictable Paridae birds this winter using a monopod. Shutter speeds 1/125s-1/160s were the norm during this session and the photos came out quite sharp and clean. That's why the VR efficiency in this range matters to me.

Here's some unprocessed example at 450mm 1/125s f/7.1 ISO-2200, moderate crop.
(zooming out was accidental, I didn't notice I moved the barrel )

View attachment 81695

Yeah, and your picture looks good, so that's working. I also gamble sometimes with DOF, leaving it at 5.6 even for something pretty close (or trying at different apertures if there is time). I have a little program that spits outs DOF at different apertures and focal lengths for my crop sensor cameras (there are of course various calculators for DOF but I wanted a nice spreadsheet). For example, at 25 feet it tells me that DOF for a 500 at 5.6 is about 1.9 inches. At 8.0, 2.7 inches. How bad do I need the extra .8 inches versus lower ISO? Sometimes I get it wrong, but it is another variable I play with when light is marginal.

The green heron picture is lightly cropped.

It's easier to go low shutter speed with the 500 pf than the 200-500 simply because it is lighter! I will also sit down and brace my elbows on my knees to get best stability at times.