Nikon Z6 auto focus trials with the Nikkor 180-600/5.6-6.3

My interest in the AF on the Z6 has been massively piqued by the release of the new Z6III. I have been thinking a lot about AF since its release, and I realised the Z6 auto focus probably is not as bad as I assumed it was for the sort of work I was doing. Not that it’s great, just not as bad as I believed.

Most of the photography I have done with the big Nikkor 180-600mm lens and requiring great auto focus is in bad light, with very small fast moving targets.

In order to test the AF on wildlife with different focus modes I headed to the south coast where there is usually a group of several hundred seagulls. This was an excellent opportunity to see how different AF modes worked, in good light, and with a range of backgrounds from sky, sea, and land.

Seagulls are good subjects as they are large, fly slowly when around the colony, and there are plenty of targets.

These are JPGs straight out of the camera with no additional editing. These weren’t selected because they’re good photos, in fact I have chosen many because they’re bad photos.

Nikon Z6, 410mm, f/6.0, 1/1000, ISO 160, -0.3EV. I needed a little more depth of field. Despite the shutter speed it is nearly OK.
Crop of the above – the Z6 pretty much nailed it, it was let down by my choice of slow shutter speed and poor tracking technique.
Nikon Z6, 410mm, f/6.0, 1/2500, ISO 800
Nikon Z6, 390mm, f/6.0, 1/2500, ISO 7200, -0.3EV

Methodology

I’ll be honest, there wasn’t much. I attempted to capture birds flying in a range of backgrounds using each auto focus mode. In short Dynamic-area and Wide-area small worked well for bird in flight, wide-ares large and Auto-AF with tracking were predictably not as good. A reminder that the Z6 does not have bird detection.

The winner this time: Wide-area AF (Small)

Wide-area AF small was the mode I spent the most amount of time in. It seemed to be the most accurate and it was pretty good at acquiring and holding focus on flying birds when against the sea or the sky. This was dependent on my tracking abilities, which are those of a complete beginner.

The runner-up: Dynamic-area AF

I spent the second highest amount of time in this mode. It was quite effective for bird in flight and stationary targets. It did appear to lock on to the background or hunt a little at times. But overall it generally quick to find birds in flight. For more or less stationary objects it was extremely quick and accurate.

Wide-area AF (Large)

I would like to try this again as my tracking ability improves, I didn’t use it for long as I struggled to acquire targets, but that was probably as much my fault as the focus modes.

Auto-area AF with subject tracking

This was a wildcard that I did not expect to work, but it did acquire focus more than I expected. Shooting sea birds on rocks, with birds and rocks looking the same, it could not match a pattern to lock onto and would move around pretty rapidly and apparently randomly.

The other issue was that even the relatively slow moving gulls were too quick to get a lock with tracking.

But it is worth trying again.

Focus Tracking with Lock-On

I tried setting this to Quick, but switched it back pretty quickly, it jumped off target too soon. Something I didn’t try but I should have, was to set it to Delayed.

Hit rate

I took 1529 images, and needed to delete 294 for being unusably out of focus. That means only 20% were unacceptably blurry. Now, there were many others of half a bird, or empty ocean, or the wrong bird in focus, and so on. The keeper rate was about 14%, and of those there are only 3 or 4 that I might publish somewhere.

Having said that the aim of the session was to push the auto focus system rather than get great shots. Many of the shots I kept are blurry to illustrate the points in this post.

Conclusions and lessons

While I defend the Z6’s AF as nowhere near as bad as YouTuber’s say it is, it certainly was not awesome, perhaps a 7 out of 10. It is usable with technique and experience. If I was solely a wildlife photographer, especially a bird photographer, the Z6 would not be my tool of choice –although the Z6III likely would be.

As I like to shoot a variety of stuff the Z6 will continue to be well suited for my needs, but I am now seriously thinking about the Z6III or Z8.

  1. I want to do this again but in a more structured way to compare the two most useful focus modes, and perhaps to the same for wide-area large and Auto-area AF without subject tracking. [Update: I have customised Geeqie’s overlay to show the focus mode making this much easier.]
  2. For bird in flight I will first try dynamic or wide-area small.
  3. I need to not rely on being at 600mm all the time.
  4. 1/1000 is too slow for bird in flight, I was getting better results with 1/2500, and given the light I should have gone faster.
  5. I should probably have stopped down a little from f6.3, as I needed a little more depth of field.

A final note: this does not compare to my usual use case of dark or high contrast environment under the forest canopy.