Z8/9 Auto Focus (C) w/Sub Detection 🐦+👁️=🧐

[Larry S.]

Hope you see this one Steve… I ran into an annoying issue with auto focus and subject detection. It finds the eye and nails the focus….in the reflection that is closer to the camera. This “yellowleg” is an example (mock-up) of what I occasionally encounter. The calmer the water the more frequently this occurs. The result is an out of focus bird if you shoot it anyway. I’ve been able to cope with this by re-framing the shot and that usually gets the eye detection back on the bird, not the closer reflection….

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[Cameron T]

More accurately, it detects the image of the bird in the water and will jump to it if you don't limit the area. This is pretty expected, especially if using a wide area mode that covers the reflection and seems to me to be working as intended (in the design).

 

[Steve]

Usually limiting the area size - as in your simulated example above - is enough to keep it on the bird. In real life, I'd be surprised if that happened like that since the main AF area wasn't on the reflected bird.

The other thing is not to use it - I tell people over and over if it's not working as expected, switch to a different AF area. I just came back from Africa and I used single point AF for 7
70% or more of max photos. When Subject Detection works, it's great, but when I start seeing it going to the wrong areas, it's over and I use something else.

 

[Larry S.]

More accurately, it detects the image of the bird in the water and will jump to it if you don't limit the area. This is pretty expected, especially if using a wide area mode that covers the reflection and seems to me to be working as intended (in the design).

The focus area does stay on the bird, but the eye detection jumps down to the reflection in the water…. I have encountered this with the wide focus area totally on the bird, not the reflection. Then eye detection jumps down to the reflected eye as above…. Just have to deal with it…

 

[Larry S.]

Usually limiting the area size - as in your simulated example above - is enough to keep it on the bird. In real life, I'd be surprised if that happened like that since the main AF area wasn't on the reflected bird.

The other thing is not to use it - I tell people over and over if it's not working as expected, switch to a different AF area. I just came back from Africa and I used single point AF for 7
70% or more of max photos. When Subject Detection works, it's great, but when I start seeing it going to the wrong areas, it's over and I use something else.

Yup, the wide mode ain’t cutting it. Thought it would if the bird launched and I needed east/west tracking. Single point will cure this on stationary critters….. I thought I recalled you presenting this focus anomaly in one if your videos… I have the video button re-programmed for focus areas and it’s really quick to move through them.

 

[Cameron T]

The focus area does stay on the bird, but the eye detection jumps down to the reflection in the water…. I have encountered this with the wide focus area totally on the bird, not the reflection. Then eye detection jumps down to the reflected eye as above…. Just have to deal with it…

Weird. I haven't had that issue with my z9. Only in auto af/etc.

 

[JAJohnson]

Hope you see this one Steve… I ran into an annoying issue with auto focus and subject detection. It finds the eye and nails the focus….in the reflection that is closer to the camera. This “yellowleg” is an example (mock-up) of what I occasionally encounter. The calmer the water the more frequently this occurs. The result is an out of focus bird if you shoot it anyway. I’ve been able to cope with this by re-framing the shot and that usually gets the eye detection back on the bird, not the closer reflection….
View attachment 87201

Like Steve, I’d be surprised if subject detection found an eye that far away from the AF box. Usually it finds heads/eyes within a zone of about 15% or so outside the box. But, strange things happen sometimes.

 

[ajrmd]

Yes, I encounter this a fair amount when shooting birds on calm waters with the right reflection conditions. Usually switching to a smaller focus area helps, but not always. Sometimes breaking and requiring the composition is the only way to resolve it. FWIW my Sony and Canon never did this.

 

[JAJohnson]

Yes, I encounter this a fair amount when shooting birds on calm waters with the right reflection conditions. Usually switching to a smaller focus area helps, but not always. Sometimes breaking and requiring the composition is the only way to resolve it. FWIW my Sony and Canon never did this.

I’ll be on the lookout for this happening so I won’t be surprised.

 

[SCoombs]

Usually limiting the area size - as in your simulated example above - is enough to keep it on the bird. In real life, I'd be surprised if that happened like that since the main AF area wasn't on the reflected bird.

The other thing is not to use it - I tell people over and over if it's not working as expected, switch to a different AF area. I just came back from Africa and I used single point AF for 7
70% or more of max photos. When Subject Detection works, it's great, but when I start seeing it going to the wrong areas, it's over and I use something else.

I've actually had this happen a fair bit using even just the 1x1 custom wide area. It doesn't always happen and while I'm not confident I feel like I want to say it has happened less since firmware 2.0, but it have definitely happened enough that it is one of the main reasons I have preferred to have a button programmed to turn off subject detection.

 

[Steve]

Yup, the wide mode ain’t cutting it. Thought it would if the bird launched and I needed east/west tracking. Single point will cure this on stationary critters….. I thought I recalled you presenting this focus anomaly in one if your videos… I have the video button re-programmed for focus areas and it’s really quick to move through them.

You can use Wide without Subject Detection too

Also, it that's really weird that it waders that far away from the AF box. I've not really had it happen too much like that and can usually cure it with a smaller Wide AF area. This is one thing I wish Nikon would change - give us the option to keep Subject Detection inside the box or not.

 

[Steve]

I've actually had this happen a fair bit using even just the 1x1 custom wide area. It doesn't always happen and while I'm not confident I feel like I want to say it has happened less since firmware 2.0, but it have definitely happened enough that it is one of the main reasons I have preferred to have a button programmed to turn off subject detection.

Happening with the 1x1 is really odd - it typically has a very limited watch area. I wonder if it's something specific to do with reflections.

 

[ajrmd]

Happening with the 1x1 is really odd - it typically has a very limited watch area. I wonder if it's something specific to do with reflections.

My less than educated guess is that it is generally nearer and tends to be brighter than the eye itself. We would need to understand the Nikon algorithms and hierarchy to know for certain.

 

[Steve]

My less than educated guess is that it is generally nearer and tends to be brighter than the eye itself. We would need to understand the Nikon algorithms and hierarchy to know for certain.

Could be - the odd thing is that normally the watch area for Subject Detection is more limited than what people are seeing when reflections are involved.

 

[SCoombs]

Happening with the 1x1 is really odd - it typically has a very limited watch area. I wonder if it's something specific to do with reflections.

If I had to guess I'd say it's probably just that it sees the bird and water as one contiguous object and so treats it as a single subject with different eyes. Have you ever had the experience where a couple of animals (or people) are overlapping in the frame and it gets confused as to what the distinct subjects are? For instance, in a situation like this I have found the camera tends to think there's a single subject.

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[Steve]

If I had to guess I'd say it's probably just that it sees the bird and water as one contiguous object and so treats it as a single subject with different eyes. Have you ever had the experience where a couple of animals (or people) are overlapping in the frame and it gets confused as to what the distinct subjects are? For instance, in a situation like this I have found the camera tends to think there's a single subject.

View attachment 87256

I'm still thinking of the watch area.

In the photo of the ducks, if you had pretty much any wide AF area on it with Subject Detection, it wouldn't surprise me to see it jump to any face (and of course, this apples to Auto and 3D). The faces are really close (good shot BTW).

However, for example, the normal watch area for a 1x1 Wide AF area is usually just a few AF points from the main AF area. So, jumping to a reflection that's halfway across the viewfinder is odd to me. I've had the system jump to reflections before, but usually they are within range of the expected watch area of the AF area.

 

[Ed Erkes]

A few weeks ago I purchased a Z8 and 800 f6.3 as a replacement for my Sony 600 which I did not like handholding. Now I go out with a Sony A1 with 200-600 and a Nikon Z8 with 800. But one thing I found out is that, despite all the firmware updates, there are still some things the Sony A1 still does much better than the Nikon Z8. ( But then there are also some things I'm finding that Nikon does better). I found the AF going to the reflection very annoying. It seldom happened with the Sony A1. The other thing I find annoying is that when photographing a pair of wood ducks, i want the camera to focus on the eye of the closest duck, but it would continually jump from one to the other. That didnt happen as often with A1. I'm tring to find out work arounds for both these issues. But I really do like the 800 f6.3. so much easier to handhold.

 

[SCoombs]

A few weeks ago I purchased a Z8 and 800 f6.3 as a replacement for my Sony 600 which I did not like handholding. Now I go out with a Sony A1 with 200-600 and a Nikon Z8 with 800. But one thing I found out is that, despite all the firmware updates, there are still some things the Sony A1 still does much better than the Nikon Z8. ( But then there are also some things I'm finding that Nikon does better). I found the AF going to the reflection very annoying. It seldom happened with the Sony A1. The other thing I find annoying is that when photographing a pair of wood ducks, i want the camera to focus on the eye of the closest duck, but it would continually jump from one to the other. That didnt happen as often with A1. I'm tring to find out work arounds for both these issues. But I really do like the 800 f6.3. so much easier to handhold.

This is interesting to read as I have previously read an extensive volume of complaints about the Sony AF system having problems with reflections and/or focus when shooting over the water.

As for the choice of duck, I've only in the past few days discovered what might be the best feature I didn't know existed on the Z8, which is the ability to program a button (I first discovered it when getting a lens that has a button on it, something I'd not had before) to switch which eye is being focused on. Now as a caveat I don't know if this will work with animals - it does work with people. If it works with animals, it might be a great tool for the situations you mention.

 

[JAJohnson]

As for the choice of duck, I've only in the past few days discovered what might be the best feature I didn't know existed on the Z8, which is the ability to program a button (I first discovered it when getting a lens that has a button on it, something I'd not had before) to switch which eye is being focused on. Now as a caveat I don't know if this will work with animals - it does work with people. If it works with animals, it might be a great tool for the situations you mention.

On Nikon mirrorless cameras, switching eyes works with animals and birds.

 

[Larry S.]

You can use Wide without Subject Detection too

Also, it that's really weird that it waders that far away from the AF box. I've not really had it happen too much like that and can usually cure it with a smaller Wide AF area. This is one thing I wish Nikon would change - give us the option to keep Subject Detection inside the box or not.

It was really weird. I’ve had the sub-det box bounce around a bit when a bird turns its’ head and the camera is hunting focus. It locks on odd stuff occasionally and gets confused. Here’s another example that occurred a couple weeks ago. I was locked down on the female osprey’s eye as the male came to the nest. She dropped her head behind a branch and the yellow sub-det box bounced around and locked on a white round object to the right. No problem here as both were in the same focus plane but the reflection issue is another matter. It might be best just to cut off the sub-det….

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[Ed Erkes]

This is interesting to read as I have previously read an extensive volume of complaints about the Sony AF system having problems with reflections and/or focus when shooting over the water.

As for the choice of duck, I've only in the past few days discovered what might be the best feature I didn't know existed on the Z8, which is the ability to program a button (I first discovered it when getting a lens that has a button on it, something I'd not had before) to switch which eye is being focused on. Now as a caveat I don't know if this will work with animals - it does work with people. If it works with animals, it might be a great tool for the situations you mention.

MOst of my experience is with wood ducks that I've been photographing on my backyard pond for about 13 years. With the Sony A1 it's been very seldom that Ive had the AF switch to the eye in the reflection. I've not really had a problem AF on water either except sometimes when there is a lot of splashing activity (ducks fighting or osprey diving into water). The AF will sometimes switch to bright water highlights.
I will have to try setting a fn button to "switch eyes" . Thanks for the suggestion.

 

[JoelKlein]

interesting discussion and good info here.
I’m thinking; what if you turn SD OFF, and navigate the 3D box on the eye. Would it track it ignoring what else is in the scene?

 

[Larry S.]

interesting discussion and good info here.
I’m thinking; what if you turn SD OFF, and navigate the 3D box on the eye. Would it track it ignoring what else is in the scene?

That’s an idea Joel, I’m going to try a few different things to sort this out. It is weird when the subject detection leaves the ranch corral to find the reflected eye..

 

[JoelKlein]

That’s an idea Joel, I’m going to try a few different things to sort this out. It is weird when the subject detection leaves the ranch corral to find the reflected eye..

Let’s try this.

 

[fcotterill]

A Dynamic mode is another alternative AF mode, although dynamic doesn't do eye detection according to Nikon.