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Dynamic AF modes in Nikon D500 very different from D800

Posted: Wed Mar 15, 2017 8:29 pm
by Ed Erkes
Finally got to try my new D500 on birds in flight a couple of weeks ago and found Dynamic AF behaving very differently than it did on my D800 (despite the fact the exact same wording is used in the two camera manuals to describe how they work).  I found that in dynamic AF modes with the d500, the focus would very quickly switch to the background if the selected focus point drifted off the subject. Function improved when I set Blocked Shot Response to 5 and subject motion to erratic. It seemed that dynamic af was behaving very similarly to single point af. I was convinced I had a defective D500 until a google search led me to this thread started by Steve Perry:  http://www.fredmiranda.com/forum/topic/1478115/0

Have others here noticed this behavior? I personally preferred the way it worked on my D800. Although using D25 or D72 and blocked shot set to 5 and subject motion at erratic, I am getting more in-focus images than I did with the D800, I think it would perform even better if it functioned as the D800 did.

Posted: Wed Mar 15, 2017 8:50 pm
by DChan
I did on quite a few occasions finding the camera focusing on the background instead of the flying pigeons even if the focus point was on the bird as far as I could tell. I'm not sure if it's me (just an average Joe here) or the camera though. Have to go read what Steve Perry is talking about.

Re: Dynamic AF modes in Nikon D500 very different from D800

Posted: Wed Mar 15, 2017 9:54 pm
by photoman4343
Ed, I use D 25 most of the time for my bird shots. Sometimes I use D72. I have not experimented much yet with the Group Area AF option, but I have read that it works well with smaller birds. I am going to try it out soon during spring migration.  

My D 500 acts like all of my other Nikon bodies. If the AF system picks up something in the background it will likely shift focus to it. And you need to respond in kind. Regarding Custom setting a3, Focus Tracking with lock on, on my D 500  I usually have Blocked Shot set to 2 or to Quick, and I keep Subject Motion to Normal or the middle position.  My style of shooting is that when I lose focus on the bird or other subject I want everything to be fast and quick. 

Please note that I use the AF ON button to focus. This is set at Custom setting a8. And I have the shutter set to release priority.  I am in AF-C mode High at 10 fps. 

When I lose focus, I just lift my finger off the AF ON button and then push it again to reacquire focus. And I use the the thumb stick to keep the focus point on the subject. Keeping that focus point right where it needs to be is extremely important. 

I do not think anyone  can make a decision about a3 without knowing the other camera settings set that may impact your overall shooting technique. This is why there usually is no simple rule that fits all for how to set a3. 

Hope this helps

Joe

Posted: Thu Mar 16, 2017 7:27 am
by E.J. Peiker
I agree with Joe. I did extensive testing on this in Ecuador and D25 is the way to go on birds in flight in most scenarios.

Re: Dynamic AF modes in Nikon D500 very different from D800

Posted: Thu Mar 16, 2017 3:20 pm
by Ed Erkes
photoman4343 wrote:Ed,

My D 500 acts like all of my other Nikon bodies. If the AF system picks up something in the background it will likely shift focus to it. And you need to respond in kind.

Joe
Joe, I'm specifically talking about the dynamic af modes on the D500. And the D500 dynamic af modes definitely behave quite differently from the dynamic af modes on previous Nikon cameras. If you read the thread started by Steve Perry, I think you'll see what I am talking about. Steve Perry also thinks that the focus lock-on parameters (such as Blocked Shot Response) interact with the D500 dynamic af modes in a different manner than they did on previous Nikon cameras.


I'm not sure why this issue has largely gone unnoticed. I tend to experiment a lot with different modes to see how they are actually working. And the D500 dynamic af modes were acting very differently on my D500 compared to my D800.

Re: Dynamic AF modes in Nikon D500 very different from D800

Posted: Thu Mar 16, 2017 5:13 pm
by Anthony Medici
Thom Hogan has stated in his guides that the dynamic AF modes of the D5 and D500 operate differently than the older cameras. On the older cameras, the camera always auto focuses the center point first and after achieving focus, it might shift to other points. (9, 25 or 51.) With the D5 and D500, if there isn't enough contrast using the point selected, it will decide to use any of the other points to lock in focus. (9, 25, 72, 153) That move is prior to the first lock on. That is probably the difference you are seeing between your D800 and D500.

Note that between the D5 and the D500, D9 mode is only available with a recent firmware update on the D5. There has not been a similar update for the D500 so it's minimum is D25.

The note is on page 486 of his D500 guide where there is no equivalent note in the D800 or D810 guides.

I'm not sure what you're referring to with Blocked Shot Response...

Thom and I travel together several times a year and have been co-instructing workshops in Botswana, Galapagos and Patagonia over the last few years.

Posted: Thu Mar 16, 2017 5:40 pm
by photoman4343
Tony, see page 665 of T. Hogan's D 500 guide. Blocked response is the first setting in Custom Setting a3.

Joe

Re: Dynamic AF modes in Nikon D500 very different from D800

Posted: Thu Mar 16, 2017 6:06 pm
by DChan
Anthony Medici wrote:With the D5 and D500, if there isn't enough contrast using the point selected, it will decide to use any of the other points to lock in focus. (9, 25, 72, 153) That move is prior to the first lock on....
So it's just like any contrast-detect AF system, i.e., if the intended target itself does not have enough contrast, the camera locks onto something with higher contrast inside the focus frame? This actually is what I feel my D500 is doing and it reminds me of the original OMD-EM5.

I did do the test suggested by Steve Perry and my D500 does not behave like what he said the D810 would do.

Re: Dynamic AF modes in Nikon D500 very different from D800

Posted: Fri Mar 17, 2017 6:57 am
by Ed Erkes
Anthony Medici wrote:Thom Hogan has stated in his guides that the dynamic AF modes of the D5 and D500 operate differently than the older cameras. On the older cameras, the camera always auto focuses the center point first and after achieving focus, it might shift to other points. (9, 25 or 51.) With the D5 and D500, if there isn't enough contrast using the point selected, it will decide to use any of the other points to lock in focus. (9, 25, 72, 153) That move is prior to the first lock on. That is probably the difference you are seeing between your D800 and D500.

No, that is not the behavior I am referring to. I have Thom Hogan's guide, but not with me right now. I'll have to check your references out. First, you are incorrect in stating that the camera always autofocuses with the center point first  in dynamic af (although you may have just misspoke and meant to refer to user selected AF point). But anyway, what I am referring to is the fact that after AF is achieved with user selected Af point, IF the subject moves off the selected AF point, the camera, after a brief delay, will switch back to the user selected focus point and focus on the background--instead of staying with the subject. With my D800, the focus  would remain on the subject indefinitely, provided there was sufficient contrast. It did not switch back to the user selected AF point unless I removed my finger from the AF-On button and then re-pressed to re-acquire focus.

Re: Dynamic AF modes in Nikon D500 very different from D800

Posted: Fri Mar 17, 2017 8:41 am
by E.J. Peiker
Ed, this is not at all what I experience with the 70-200E, Sigma 150-600, and 16-80mm lenses.  In my experience, using D25 or D72, once you obtain focus, as long as the area that you are focusing on remains anywhere in the array of focus points selected, everything stays in focus.  I shot literally thousands of shots of birds in flight in Ecuador using this and not a single shot missed focus as long as I kept the focus area anywhere in the selected array of AF points, literally not one and I never had the camera go for the background.  here are my settings:
AF-C
D25 or d72
a1 - Release
a3 - 2, motion in the default center position
a5 - WIDE (irrelevant to this discussion)
a6 - 55
a12 - On, On, N/A, N/A

Re: Dynamic AF modes in Nikon D500 very different from D800

Posted: Fri Mar 17, 2017 10:08 am
by DChan
E.J. Peiker wrote: I shot literally thousands of shots of birds in flight in Ecuador using this and not a single shot missed focus as long as I kept the focus area anywhere in the selected array of AF points,
In Steve Perry's opinion, you won't see the focus going to the background if your background is the blue sky. Was that the case with your BIF shots?? I think if the bird is large in the frame you won't see the shifting-to-the-background happen.

My understanding of what Steve Perry was referring to is that in D25, etc., the D500's AF does not track the target (like 3D tracking ) within the D25 box while D810's does. My test confirmed his findings.

Re: Dynamic AF modes in Nikon D500 very different from D800

Posted: Fri Mar 17, 2017 11:23 am
by Ed Erkes
DChan wrote:
E.J. Peiker wrote: I shot literally thousands of shots of birds in flight in Ecuador using this and not a single shot missed focus as long as I kept the focus area anywhere in the selected array of AF points,
In Steve Perry's opinion, you won't see the focus going to the background if your background is the blue sky. Was that the case with your BIF shots?? I think if the bird is large in the frame you won't see the shifting-to-the-background happen.

My understanding of what Steve Perry was referring to is that in D25, etc., the D500's AF does not track the target (like 3D tracking ) within the D25 box while D810's does. My test confirmed his findings.
No, dynamic af seems to work fine on clean backgrounds like blue sky. The only action photography I've done so far with my new d500 has been photographing wood ducks taking flight from my backyard pond, often with grasses and trees in the background. It is with the closer backgrounds where I was particularly having trouble. 

Re: Dynamic AF modes in Nikon D500 very different from D800

Posted: Fri Mar 17, 2017 12:57 pm
by DChan
Ed Erkes wrote:
No, dynamic af seems to work fine on clean backgrounds like blue sky. The only action photography I've done so far with my new d500 has been photographing wood ducks taking flight from my backyard pond, often with grasses and trees in the background. It is with the closer backgrounds where I was particularly having trouble. 

I just did a quick test with my D500 focusing on a construction crane with nothing but a cloudy sky in the background. I selected the center point as the focus point, focused on the crane and started moving the camera around. The focus point did not move one bit. It did not shift focus to the background as far as I can tell, but it also did not shift the focus point back to the crane when it had been moved away from the crane because of the movement of my camera. There was no tracking happening. This is the same result that one will get simply using single point focus. The only AF mode that does tracking is 3D tracking.

I photographed flying pigeons in busy streets and I got shots with focus on the background instead. Not all the time but it happened.

Some has suggested that "group" is good for small birds. My experiences suggest otherwise unless it's with a clean background or distant background. With messy background, single point is more reliable.

Re: Dynamic AF modes in Nikon D500 very different from D800

Posted: Fri Mar 17, 2017 1:49 pm
by Ed Erkes
E.J. Peiker wrote:Ed, this is not at all what I experience with the 70-200E, Sigma 150-600, and 16-80mm lenses.  In my experience, using D25 or D72, once you obtain focus, as long as the area that you are focusing on remains anywhere in the array of focus points selected, everything stays in focus.  I shot literally thousands of shots of birds in flight in Ecuador using this and not a single shot missed focus as long as I kept the focus area anywhere in the selected array of AF points, literally not one and I never had the camera go for the background.  here are my settings:
AF-C
D25 or d72
a1 - Release
a3 - 2, motion in the default center position
a5 - WIDE (irrelevant to this discussion)
a6 - 55
a12 - On, On, N/A, N/A
My settings were essentially the same as yours except I had a3 on 3 instead of 2. I'm now setting a3 to 5 (delayed) and subject motion to erratic. According to Steve Perry that may slow down how quickly the active af point reverts back to the user selected or primary af point. You can easily see the point of focus switch back to the primary af point by setting up a more static test situation (as described in the link in my initial post). Then perform the same test with a D800 or D810 and you'll see how different the cameras behave in dynamic af.

Re: Dynamic AF modes in Nikon D500 very different from D800

Posted: Fri Mar 17, 2017 3:34 pm
by E.J. Peiker
DChan wrote:
E.J. Peiker wrote: I shot literally thousands of shots of birds in flight in Ecuador using this and not a single shot missed focus as long as I kept the focus area anywhere in the selected array of AF points,
In Steve Perry's opinion, you won't see the focus going to the background if your background is the blue sky. Was that the case with your BIF shots?? I think if the bird is large in the frame you won't see the shifting-to-the-background happen.

My understanding of what Steve Perry was referring to is that in D25, etc., the D500's AF does not track the target (like 3D tracking ) within the D25 box while D810's does. My test confirmed his findings.
Nope, it's all vegetation.