13. Autofocus Performance
Although the Nikon Z7 sports a completely new 493-point autofocus system, it still shares a lot of focusing DNA with Nikon’s DSLR lineup – although not necessarily in a good way. Nikon DSLRs, especially the newest models, are known for their high-quality phase detect autofocus systems when shooting via the viewfinder. But that reputation doesn’t carry over to live view autofocus performance, which – even on Nikon’s best DSLRs – is really just so-so.
The Z7’s autofocus is a bit of a blend between Nikon’s traditional viewfinder and live view focusing systems, although it bears more similarities to the live view implementation. The good news is that the addition of on-sensor phase detect pixels lets the Z7 focus quite quickly, and other features like subject tracking and Low-Light AF are better than Nikon’s earlier live view attempts.
The bad news is that the Z7 focus system is, still, just an improved version of Nikon’s live view autofocus. It isn’t at the same level as the 153-point phase detect system found in the Nikon D5, D850, and D500, or even the 51-point system found in older Nikon DSLRs – particularly in terms of tracking capabilities. You’ll also find the DSLR autofocus layout and options to be much more extensive and logical, while the Z7 includes some peculiar handling choices in this respect.
For instance, here is a comparison between the autofocus area mode options on the Nikon D850 and Nikon Z7:
|AF Area Mode||Nikon D850||Nikon Z7|
|Pinpoint||Yes (in live view only)||Yes|
|9-Point Dynamic Area||Yes||Yes|
|25-Point Dynamic Area||Yes||No|
|72-Point Dynamic Area||Yes||No|
|153-Point Dynamic Area||Yes||No|
|Wide-Area AF||Yes, one size (and live view only)||Yes, both L and S sizes|
|3D Tracking||Yes||Yes, hidden under Auto Area|
As you can see, the D850 clearly comes out ahead. The Z7 doesn’t have D25, D72, or D153 dynamic-area AF points. Nor does it have Group Area AF. And although both cameras have 3D tracking, its implementation – as discussed in a moment – is more awkward to use than that of the D850, hidden under the Auto Area AF mode rather than as a separate option of its own.
The Nikon Z7 doesn’t have a dedicated button to change autofocus settings. This is a departure from Nikon’s classic design choice, to have an AF-M switch on the front of the camera with an autofocus button inside. In its place, Nikon expects you to use the quick menu – accessed via the “i” button – to change focusing settings, or otherwise assign a custom button for that purpose.
Personally, I’ve chosen to assign my movie record button to change autofocus settings, and it’s not a bad solution. Press the button and spin one dial to change between AF-S, AF-C, and MF. Spin the other dial to change autofocus area modes, such as Auto Area, 9-Point Dynamic Area, Wide Area, Pinpoint (only in AF-S), and so on. Of note is that the Z7 does not have an AF-A mode to switch automatically between AF-S and AF-C, which is not a big deal for most of this camera’s users, but nonetheless matters to some photographers.
Once you assign autofocus settings to a good custom button, you’ll find that the Z7 works in much the same way as other Nikon cameras. Of course, assigning a button for this purpose does prevent you from using it for a different custom function, which isn’t ideal. As mentioned earlier, this takes away a spot to assign something like metering or bracketing. Still, if you change autofocus settings frequently, assigning a custom button is much better than entering the “i” menu all the time.
Lastly, note that you cannot use the Z7’s LCD touchscreen to control your autofocus point while looking through the viewfinder. Other mirrorless cameras have this capability, and some photographers have noted it to be a useful part of their shooting styles. Personally, I prefer the joystick instead, and I wouldn’t use the touchscreen for this purpose even if it were available. But if this is a feature you think you would use, just keep in mind that the Z7 doesn’t have it – at least at the moment. A firmware update could conceivably add this capability.
13.2 AF-S Performance (Static Subjects)
The Z7’s autofocus is superb for static subjects, focusing quickly and accurately, including in low-light conditions. You’ll still want to find a subject with good texture, though, not just a single sharp line or soft transition. And, as covered more in a moment, you get the best performance using native Z lenses rather than F-mount lenses via the FTZ adapter.
With the native 24-70mm f/4 S and 35mm f/1.8 S lenses, the Z7’s AF-S (single servo autofocus) is simply excellent and very accurate. In fact, when compared to DSLR performance with prime lenses, the focusing performance of the Nikon Z7 is superior for a number of reasons. First of all, unlike DSLR cameras that have a separate phase-detection autofocus system that does not always match the lens, mirrorless cameras focus right on the sensor plane. This basically eliminates focus variances between the camera body and the lens and removes the need for fine-tuning lenses.
Second, unlike DSLR cameras that require lenses to always focus at their widest apertures (to keep the viewfinder bright and to allow maximum light to reach the phase detection system), which results in focus shift issues, the Nikon Z7 stops the lens down to the exact aperture before it focuses, which pretty much eliminates focus shift. Electronic viewfinders and LCD screens are able to compensate for the reduced amount of light by boosting their brightness, something that is not possible to do on an optical viewfinder. It is important to note that the stopping down happens only at larger apertures that are prone to focus shift (from maximum aperture to f/5.6). When using smaller apertures like f/8-f/22, the camera keeps the lens locked at large enough aperture to pass sufficient light to the sensor, then stops the lens down to the desired aperture right before the image is captured. This is a very smart way of mitigating focus shift on the Z7, which drastically reduces focusing issues.
Lastly, I personally found the Nikon Z7 to focus extremely accurately on a high-contrast test target when using Imatest software, which was very impressive. When testing with a DSLR, although I can often count on the contrast-detection AF when using live view, it often fails with some lenses and I have to manual tweak focus afterwards. With the Nikon Z7, I have not encountered a single case where I had to tweak focus – it was pretty much “dead-on” every single time. This made the process of evaluating lenses easier, although there were some big annoyances that I wish weren’t there, which I will cover in the next section below.
Overall, autofocus speed and accuracy are quite impressive, with practically no hunting for focus at all under most conditions. You have several autofocus area modes to choose from for AF-S, including a “Pinpoint” area mode previously found only on the D850 in live view. This is a great way to set an extremely small focusing box to lock onto a very precise subject. It takes a bit more time to autofocus when you use this method, so I personally prefer the slightly larger area mode by default, but this is a nice way to make sure that you are targeting your exact subject – for example, the center of a flower rather than its petals.
One missing feature on the Z7 compared to other mirrorless cameras, however, is the lack of “Eye AF” – the ability to prioritize focus on a person’s eye, not just their face in general. This applies both to AF-S and AF-C, but either way, you won’t find it on this camera. Instead, there is a more generic face tracking option, which certainly can result in sharp focus on the eyes, but it isn’t always perfect. This is one feature which a lot of photographers have asked for in a firmware update or the next version of the Z7, and I have to agree.
Aside from that, though, the Z7 is excellent overall for stationary subjects. Especially if you already prefer shooting in live view, such as many architectural and landscape photographers, you’ll find the Z7’s AF-S to beat most other options on the market for focusing on a non-moving scene. It’s fast and accurate, and it has enough options to make autofocus easy even in tricky conditions.
13.3 AF-C Performance (Moving Subjects)
Although the Z7 does a great job at single-servo autofocus, continuous autofocus is more of a mixed bag. That’s especially true when you try to track your subject across the frame. Although it does a better job locking onto and following your subject than Nikon DSLRs in live view, it is far from perfect and frequently misses focus in a series of AF-C images. Note that it is hardly the worst tracking performance for a mirrorless camera, and you definitely can get good photos shooting AF-C, but it still lags behind DSLRs significantly.
That’s especially true in dark conditions, since the low-light AF simply doesn’t engage in AF-C mode (and even if it did, it wouldn’t be nearly fast enough to keep up with a moving subject). You’ll need to switch back to AF-S if you want any chance of the camera locking on in dark environments.
Previous Nikon users might find another thing odd: In AF-C mode, the red box that indicates proper focus never turns green, even when the photo is completely sharp. Instead, it stays red and unchanging the entire time, unless the Z7 has completely failed to find focus, at which point the box starts blinking. Although this isn’t unworkable behavior, it’s a bit disconcerting if you’ve internalized that red means out of focus and green means tack-sharp.
Even weirder, though, is the way to lock onto a subject and track it across the frame. On Nikon DSLRs, this is known as 3D Tracking; on the Z7, it’s accessed under “Auto-Area AF” instead. Once you’re in Auto-Area, you need to press the center “Ok” button in order to bring up a box to position over your subject. Move it around and press Ok again, or start focusing (either by half-pressing the shutter button or by pressing AF-On), and the Z7 will lock onto that subject and follow it around. To change subjects, you need to press the Ok button another time, which will reset the box to the center of your frame and begin the whole process again.
Sounds confusing? It is. In practice, even though it doesn’t take long to internalize the setup process, the whole thing never quite stops being awkward. Keep in mind, too, that this is the only way to track your subject across more than just nine focusing points. So, it’s likely something that most photographers will use at some point.
On balance, the Z7 really is not good at continuous autofocus or tracking your subject. It can work in a pinch or if your subject is moving slowly, but it won’t track your subject at the level we’ve come to expect from Nikon’s top-of-the-line DSLRs. In fact, as harsh as it sounds, I would argue that the overall AF-C performance even on entry-level Nikon cameras like the D5600 is better than this.
13.4 Low-Light AF
The new “low light AF” feature on the Z7 uses longer shutter speeds to gather more light, creating a brighter image preview in order to help the autofocus system lock on in dark environments. The downside is that it can take quite a bit of time to focus when using the low-light AF feature, and the image preview becomes quite laggy as a result of the longer shutter speeds. To me, those downsides don’t matter too much, because the low-light AF feature lets the Z7 shoot in much darker conditions than would otherwise be possible.
The Z7 focuses best on high-texture areas, so make sure to find subjects with as much contrast as possible when you want to use this feature. If you find a good subject, you’ll be able to use the Z7 in remarkably dark conditions to lock focus precisely. I took the photo below with an f/4 lens under moonlight and a bit of residual light from blue hour, autofocused on the texture in the hills – no problem with this camera:
In fact, I like the brighter preview so much that I wish you could use it while focusing manually, particularly for something like Milky Way photography. As good as the Z7’s low-light AF can be, it still won’t autofocus on a star in the dark of night. That’s no surprise, of course; I wouldn’t expect such insane performance, even though the Fuji X-T3 somehow manages to make it work. But I would love to have the brighter preview available for manual focus work, since it’s not easy to pinpoint a star at night based on the normal LCD image. This, too, could be added with a firmware update, and it would be a very welcome sight.
13.5 Adapted Lenses
When adapting F-mount lenses onto the Z7 via the FTZ adapter, focus performance noticeably declines. Low-light AF doesn’t work in conditions that are quite as dark, for one. And you’ll find the Z7 giving up more quickly in general, regardless of lighting conditions. You need to be more careful about your subject and find something with as much contrast as possible. Accuracy stays quite high when it does lock on, though.
It’s not actively bad, and it certainly succeeds more than it fails, but at the same time you can tell that the Z7 was made for native lenses. Even the speed of focusing is slower with the FTZ adapter compared to the fly-by-wire system in Z lenses. That wouldn’t be as big of a problem if more Z lenses were available, but at the moment there isn’t even a native lens more than 70mm for the Z7 (and the only telephoto on their roadmap beyond 85mm is a 70-200mm f/2.8). So, if you’re eager to make the Z7 your main camera system, you better be willing to accept the somewhat worse focusing performance with the FTZ adapter.
Again, I’ll emphasize that these issues are not going to ruin your day-to-day photography. The autofocus performance from the FTZ adapter is not vastly worse; it’s just a step down. You can still get plenty of good photos from adapted lenses, generally without focusing issues at all. But if you tend to push against the boundaries of the Z7’s focus system anyway, you’ll run into problems sooner when you adapt a lens.
13.6 Is the Z7’s Autofocus Good Enough?
Let’s say you’re a D850 shooter, and a group of Nikon engineers offers to build you a better version of live view autofocus. It’s noticeably faster, adds some extra tracking options, and works in lower light than before. But these improvements come at a cost: the only way to implement the new version of live view is to scrap the old, highly praised viewfinder autofocus system completely. For better or worse, both in live view and the viewfinder, you’re stuck with the new focusing system. Would you make the swap? Because that’s about where the Z7 is.
It’s not a scenario that many photographers would openly embrace, although I’ll caution that it’s not as bad as you might think. After all, a significant number of landscape and architectural photographers are using live view for most photos anyway. With this change, your live view autofocus system is more responsive overall, and it works better in low light conditions. Perhaps that’s more important to you than the advantages of the old viewfinder autofocus system. And, similarly, video shooters should welcome the better tracking for moving subjects, improving the camera’s usability by a significant degree.
Even if you’re a portrait or travel photographer, you might find that the new setup works just fine for your typical photography. That’s because, with some exceptions, you probably weren’t pushing the tracking and speed capabilities of your current autofocus system to its limits. Although you don’t gain much from this swap, you probably don’t lose anything critical to your everyday work.
It’s really the sports and wildlife photographers who should decline this offer outright. Nikon’s newest 153-point phase detection system – the one you’ll find on the D850, D5, and D500 – is excellent. It is perhaps the best autofocus system on the market today, and the older 51-point system isn’t much far behind. Although no one would say no to a better version of live view, photographers who rely on Nikon’s top-notch phase detect autofocus will lose a lot more than they gain from this deal.
And that brings us back to the Z7. Despite some flaws, its autofocus is better than the live view system of any current Nikon DSLR. It works in lower light conditions and tracks subjects better, as well as nailing focus more quickly in the first place (particularly with native Z lenses). If you’re a live view shooter, you’ll like this camera a lot.
But anyone who pushes their viewfinder phase detect system to its limits should be cautious about buying the Z7. Even when you configure the Z7’s custom buttons in a familiar way, its autofocus system is still less intuitive than what you’ll find on a Nikon DSLR (largely because of the strange method to enable 3D tracking). And that’s a separate issue from the quality of the focusing system itself, which works well for static and slower subjects but has issues tracking fast-moving subjects with perfect accuracy.
Then again, photographers often assume they need higher-end specifications than they really do. Sure, there is a clear difference in autofocus performance between the Z7 and a DSLR like the D850, but it only matters for some photographers – and you probably already know if you’re one of them. Here’s one litmus test: If you look at medium format cameras and laugh, knowing they would be completely useless for your fast-paced work and never even wishing you had one, don’t get the Z7.
On the other hand, if you don’t need to track fast-moving subjects very often, the Z7’s focusing system probably isn’t a dealbreaker. In fact, if you primarily use live view for your photography, the Z7’s autofocus actually has some significant benefits over many of Nikon’s other cameras. That’s not to excuse the autofocus flaws you’ll find on the camera – just a reminder that everyone’s needs are different.
13.7 Autofocus Summary
In short, compared to Nikon’s usual live view autofocus, the Z7 is a clear step up, especially when it comes to single servo focusing where the camera even beats its DSLR counterparts. However, compared to the phase detect system found on cameras like the D850 and D5 for subject tracking, it is a definite step down. You’ll get fast and accurate autofocus on static subjects with the Z7, no doubt, including with adapted lenses (though native ones are better). But when you try to track moving subjects around the frame, the Z7 clearly lags Nikon’s top DSLRs. That might not matter to every photographer, but it certainly does to some. Make your purchasing decision accordingly.
14. Shooting Speed (FPS) and Buffer
The Nikon Z7 is capable of shooting at up to 9 frames per second, although that frame rate comes with some important limitations. You cannot shoot 14-bit RAW – only 12-bit – and exposure is locked to the first frame in your sequence. By shooting at 8 FPS, you gain back the ability to set 14-bit RAW. But it isn’t until you’re down to 5.5 FPS that you get back Auto Exposure after the first photo in your burst.
If you always shoot Manual, this doesn’t matter anyway, since you won’t be using Auto Exposure in the first place. But if you like shooting in Aperture Priority, the lack of AE can be quite annoying. It depends upon the burst, but this can result in some blown-out highlights later in your series if you aren’t careful – say, you’re photographing a bird that flies in front of a bright cloud.
Still, keep in mind that 9 FPS, even with limitations, is pretty impressive for a 45-megapixel camera. Each 12-bit lossless compressed RAW file is around 44.7 megabytes; that’s a lot of data to process. Unfortunately, though, the Z7 buffer doesn’t do a great job keeping up with all this information. You’ll only get about 23 photos at 9 FPS shooting (totaling less than three seconds before the camera slows down), or 19 photos at 8 FPS and 14-bit RAW. Here is the full chart, comparing the Z7 to the Z6, D850, D810, and D800:
|DSLR||Image Type||File Size||Buffer|
|Nikon Z7||NEF (RAW), Lossless compressed, 12-bit||44.7 MB||23|
|Nikon Z6||NEF (RAW), Lossless compressed, 12-bit||22.5 MB||35|
|Nikon D850||NEF (RAW), Lossless compressed, 12-bit||41.5 MB||170|
|Nikon D810||NEF (RAW), Lossless compressed, 12-bit||31.9 MB||47|
|Nikon D800 / D800E||NEF (RAW), Lossless compressed, 12-bit||32.4 MB||21|
|Nikon Z7||NEF (RAW), Lossless compressed, 14-bit||55.8 MB||19|
|Nikon Z6||NEF (RAW), Lossless compressed, 14-bit||28.2 MB||43|
|Nikon D850||NEF (RAW), Lossless compressed, 14-bit||51.5 MB||51|
|Nikon D810||NEF (RAW), Lossless compressed, 14-bit||40.7 MB||28|
|Nikon D800 / D800E||NEF (RAW), Lossless compressed, 14-bit||41.3 MB||17|
|Nikon Z7||NEF (RAW), Compressed, 12-bit||40.7 MB||23|
|Nikon Z6||NEF (RAW), Compressed, 12-bit||20.4 MB||37|
|Nikon D850||NEF (RAW), Compressed, 12-bit||34.2 MB||200|
|Nikon D810||NEF (RAW), Compressed, 12-bit||29.2 MB||58|
|Nikon D800 / D800E||NEF (RAW), Compressed, 12-bit||29.0 MB||25|
|Nikon Z7||NEF (RAW), Compressed, 14-bit||49.4 MB||19|
|Nikon Z6||NEF (RAW), Compressed, 14-bit||24.8 MB||43|
|Nikon D850||NEF (RAW), Compressed, 14-bit||43.8 MB||74|
|Nikon D810||NEF (RAW), Compressed, 14-bit||36.3 MB||35|
|Nikon D800 / D800E||NEF (RAW), Compressed, 14-bit||35.9 MB||20|
|Nikon Z7||NEF (RAW), Uncompressed, 12-bit||74.1 MB||23|
|Nikon Z6||NEF (RAW), Uncompressed, 12-bit||38.5 MB||33|
|Nikon D850||NEF (RAW), Uncompressed, 12-bit||70.3 MB||55|
|Nikon D810||NEF (RAW), Uncompressed, 12-bit||55.9 MB||34|
|Nikon D800 / D800E||NEF (RAW), Uncompressed, 12-bit||57.0 MB||18|
|Nikon Z7||NEF (RAW), Uncompressed, 14-bit||85.1 MB||18|
|Nikon Z6||NEF (RAW), Uncompressed, 14-bit||44.1 MB||34|
|Nikon D850||NEF (RAW), Uncompressed, 14-bit||92.0 MB||29|
|Nikon D810||NEF (RAW), Uncompressed, 14-bit||73.2 MB||23|
|Nikon D800 / D800E||NEF (RAW), Uncompressed, 14-bit||74.4 MB||16|
|Nikon Z7||JPEG Fine (Large)||17.2 MB||25|
|Nikon Z6||JPEG Fine (Large)||9.4 MB||44|
|Nikon D850||JPEG Fine (Large)||22.0 MB||200|
|Nikon D810||JPEG Fine (Large)||18.1 MB||100|
|Nikon D800 / D800E||JPEG Fine (Large)||16.3 MB||100|
As we have already discussed on the first page of the review, compared to the D850, the Z7 clearly lags in buffer performance. For just one example, at 14-bit lossless compressed RAW, it’s a difference between 19 and 51 images before the camera slows down. The D850 looks even better by comparison when shooting 12-bit lossless compressed RAW, at which point it gets a whopping 170 images compared to the Z7’s 23 before slowing down. The good news for mirrorless lovers is that the Z7 doesn’t lock up completely when the buffer fills, and even continues around 3-4 FPS. So, although the buffer numbers aren’t very good, at least the Z7 doesn’t freeze up completely after a few seconds of continuous shooting.
One last thing to note is viewfinder blackout. Despite earlier reports to the contrary, the Z7 does not go completely dark when you shoot at fast frame rates. Instead, at 9 FPS, you’ll see a near-live preview of the scene, but with the viewfinder image only refreshed at 9 FPS. So, it’s jerky, but you’ll see the scene. At 8 FPS and slower, the viewfinder image will go black for a fraction of a second during individual frames, but the rest of the time will be live and quick to refresh – not too different from shooting with a DSLR when the mirror moves out of the way in mid burst. The key is that you need to turn ON “View all in continuous mode” in the Shooting/Display section of the Custom Setting Menu.