AF usability & new system explained

Key Takeaways:

  • AF modes differ from Nikon DSLR's, which can be jarring.
  • AF points are easily visible.
  • AF Tracking, available from Auto area mode, can be cumbersome to engage and use.
  • Auto Area mode tends to prioritize distant subjects, rather than near ones.

Aufofocus control

The AF system in the Z7 is an evolved version of Nikon DSLR's Live View mode, which might confuse hardcore Nikon users. It can also be more cumbersome to operate than the company's DSLR AF system (more on that here).

This has the advantage that the autofocus system is highly consistent between stills and video shooting, but we've found it slower and less effective than the system on Nikon's DSLRs in through-the-viewfinder shooting, as well as unfamiliar.

AF Modes:

  • Pinpoint AF (AF-S only)
  • Single Point
  • Dynamic Area (AF-C only)
  • Wide S
  • Wide L
  • Auto

Single point

Dynamic

Dynamic Area is most similar to the 'Dynamic 9' mode on Nikon's DSLRs, while Wide S and Wide L are increasingly larger areas than single point. Wide L ends up being slightly larger than the 'Dynamic' area. As on Nikon's DSLRs the chosen point is always shown in red, to ensure visibility.

When shooting we didn't find the Wide modes especially useful and would much rather have seen a choice of 'Dynamic' mode sizes, or the 'Group AF' as you get on Nikon's DSLRs.

Auto area and Tracking

The Auto area makes use of the entire frame and should give emphasis to things nearby and near the center of the frame. It will prioritize faces if you have face detection enabled.

If more than one face is found, the camera will display an arrow on the face target, to indicate which directional button to press to select the other face.

AF Tracking is available from Auto area mode. To engage Tracking mode you need to press the OK button (when using the viewfinder) or tap on the screen to select a subject. Half-pressing the shutter or hitting OK again will track the subject. However, unlike the '3D Tracking' in Nikon's DSLRs, you need to press OK again to reset the point, rather than just pressing the shutter to start tracking and releasing it to reset.

The Z7's AF Tracking system is a lot slower to use than on Nikon's DSLRs, especially when trying to rapidly switch between subjects.

The Z's system is a lot slower to use than the comparable feature on Nikon's DSLRs, especially when trying to rapidly switch between subjects. This is partly because it requires you to move your thumb to actively disengage tracking (by pressing 'OK' again or tapping onto a new subject), and partly because the point then reverts to the center of the screen, not where you originally positioned it (if you were anticipating action from a certain part of the frame). On Nikon DSLRs, simply disengaging the shutter button returns the AF point to your selected one, after which you can immediately place it over any other subject to initiate focus on it.

To make matters worse, to leave tracking mode and get back to Auto area, you need to press the (nearly unreachable) 'Zoom Out' button.

Low light AF mode

The Z7 offers a Low-Light AF mode in AF-S shooting. This mode is especially handy for tripod shooting in very dark scenarios - focus speeds are slow, but precise. It can be engaged from within Autofocus custom settings menu.


AF-S usability

AF-S performance is precise and snappy.
ISO 64 | 1/640 sec | F1.8 | Shot with the Nikon Z 35mm F1.8 S
Photo by Dan Bracaglia

AF-S performance is snappy and precise. The 'Single Point' is a nice size for a lot of shooting, and it's bright red so it's always visible.

To make it quicker to move and select an AF point with the joystick or touchscreen, there's an option to limit point selection from 493 points to every alternate point, meaning you only have about a quarter as many points (135) to navigate. Most photographers are likely to find this gives enough locational precision for most shooting.

Pinpoint AF is very precise but can be unusably slow

However, those times you do need a very fine point in a very specific location: a small bird between branches, or a subject's eye (in the absence of any eye-detection system), you'll need to use 'Pinpoint AF'. This is contrast-detection only, so is very precise but prone to hunting. In fact, we found it generally to be unusably slow, both in terms of positioning the point and in that our subject had usually moved before focus was acquired.

The good news is that the AF-S system is otherwise pretty quick, without an obvious speed penalty for its precision-enhancing contrast detection step. Oddly we found some adapted F-mount lenses would focus faster than the initial Z-mount lenses.

We found it would sometimes focus on the background and ignore closer subjects

We didn't have so much luck with Auto area mode. We found it would sometimes focus on the background and ignore closer subjects and we that engaging Face Detection mode made things worse as it would regularly register a 'false positive' and focus on a distant balloon or chair leg.

The experience of selecting between faces ends up feeling like a video game

We also had problems when trying to select between multiple detected faces. All it takes is for one of the subjects to look away and you lose the option to select it. The experience ends up feeling like a video game, trying to hit the arrow key as quickly as the camera provides the option, just it case it disappears again.

AF-C with tracking - usability

Subject tracking, or the ability of the AF system to recognize and follow your chosen subject around the frame no matter where it moves to, can be a very useful feature. It means you can concentrate on composition, not keeping your subject under the focus point. 3D Tracking on Nikon DSLRs is the current gold standard in this regard.

Half-pressing the shutter to track and releasing it to reset the AF point to your previously chosen position is pretty much the standard way to operate: Sony's Lock-On AF and Olympus's C-AF + TR modes work the same way.

Half-pressing the shutter to track and releasing to reset the AF point is pretty much the standard way to operate, this is not matched by the Z7

As described above, this is not matched by the Z7. Selecting your subject is slower and disengaging to select a different subject is slower. And, because the Z7 doesn't let you assign an AF mode + AF-On to a button, you can't just override the current mode to dip in and out of tracking - or any other AF - mode, the way you can on a Nikon DSLR or on Sony's latest-gen mirrorless.

Watch the video above from 0:54 onward to understand how the AF modes, and subject tracking in particular, differs between the Z7 and Nikon DSLRs.

Flash AF Illumination

Our final frustration with the Z7's autofocus behavior is one that's common across mirrorless cameras: the failure to fire the AF illumination lamp on external flashguns. There are some technological reasons for this, but it's still a major drawback for anyone shooting key-moment photographs in low light conditions. Especially with a camera that struggles in low light as much as the Z7.

Click here to find our why we think this is so important.

Conclusion

We're somewhat perplexed as to why Nikon went to the effort of recreating the exact look of some of its AF modes (Single and Dynamic) yet throw away the others that it's developed over the years. Likewise, it seems perverse for Nikon to not imitate the behavior of its 3D Tracking mode, which we consider industry-leading, only to replace it with something slower and more awkward.

The differences in performance are almost easier to accept, since its live view AF system - even when it underpinned the likes of the Coolpix A's operation - hasn't previously been expected to deliver competitive performance for high speed shooting. But, while performance shortcomings are likely to improve with iteration, it's harder to forgive discarding the experience that had been carefully honed over decades of development and feedback from professionals.