Is Six Greater Than Seven?
The price tag drops it right in the middle of stiff competition from all the key mirrorless camera protagonists, but Nikon’s Z 6 looks to be up to the challenges. To start with, it has many of the Z 7’s goodies.
We may have had to wait a perplexingly long time for Nikon to get its act together with a high-end mirrorless camera system, but after testing the flagship Z 7… well, all is forgiven, isn’t it? It’s a brilliant interpretation of the mirrorless brief while still avoiding too much of a culture shock for D-SLR traditionalists. Even if you’re deeply in love with your D850, I defy you not to be seduced by the Z 7… it does everything just as well, but is smaller, lighter, faster and quieter. There’s been some nit-picking about the AF tracking performance, but frankly it’s nothing more than nit-picking.
But wait, there’s more.
The Z 7 was, of course, launched along with the Z 6 which shares exactly the same chassis, body and control layout, but is built for speed… more speed, that is. Nikon calls the Z 7 “The Perfectionist” (which, in truth, really isn’t too much hyperbole) and the Z 6 “The All-Rounder”.
Side-by-side you can’t tell them apart (except for the model badge), but on the inside there’s a few significant differences which make the Z 6 faster than its sibling… and quite a bit cheaper into the bargain. We suspect that the Z 6 is going to be the volume seller of the pair because, let’s face it, not everybody needs (or even wants) 47 megapixels worth of resolution, and you’re looking at an outlay of at least $6500 for the body with the Nikkor Z 24-70mm f4.0 standard zoom and the must-have FTZ converter for all your F mount lenses. You can lop two grand off the bottom line if you opt for the Z 6 in the same kit configuration and you’re still getting a lot of what the Z 7 offers, including the all-metal weather-sealed bodyshell, 3.68 megadots EVF, touchscreen monitor, five-axis sensor-shift image stabilisation, 4K video with a 10-bit HDMI output, and all the usual higher-end Nikon image processing functions.
Less Is More
The sensor – designed by Nikon, but fabricated by somebody else – is still a 35mm format backside-illuminated (BSI) CMOS that’s mated with Nikon’s latest ‘Expeed 6’ processor, but now with an optical low-pass filter. The total pixel count is 25.28 million, giving an effective count of 24.5 million.
In reality, this is still quite sufficient resolution for numerous applications, ensuring good definition and detailing at the lower sensitivity settings in prints up to A0 in size. If you’re familiar with Nikon’s D-SLR family, you’ll note these are similar specs to the D750 and the Z 6 is essentially the mirrorless alternative to this model as the Z 7 is to the D850. Of course, the D750 is starting to get a bit long in the tooth now and both the sensor and the processor in the Z 6 are several generations down the track – with all the attendant performance benefits – but you get the idea. Additionally, the Z 6’s sensor not only employs the BSI architecture to optimise sensitivity (and hence improve the signal-to-noise ratio), but also incorporates on-sensor pixels for phase-difference detection autofocusing, giving much greater frame coverage (around 90 percent both horizontally and vertically).
For the record, the Z 6’s pixels are sized at 5.94 microns versus 4.34 microns for the Z 7. These bigger pixels deliver an increased sensitivity range which spans the equivalent of ISO 100 to 51,200 with extensions either side to ISO 50 and 204,800. Given that the Z 7 is such an exceptional high-ISO performer – at least up to ISO 6400 – on paper at least, the Z 6 should do even better… we shall see.
The lower resolution means smaller file sizes and hence the potential for faster shooting which is enhanced by the extra speed of Nikon’s latest processor so the Z 6 can hit 12 fps compared to 9.0 fps for the Z 7 and just 6.5 fps for the D750. In fact, if you want 12 fps shooting from a Nikon D-SLR you have to step up to the pro-level D5 which is still selling for around $9000 for the camera body only. However, there are some caveats with the Z 6’s speed because while 12 fps comes with frame-by-frame autofocusing adjustment, mysteriously the exposure is still locked to the first frame (as is also the case with the Z 7). With full AF and AE adjustment, the continuous shooting speed drops to a more modest 5.5 fps. Additionally, with 14-bit RAW capture, the top speed is reduced to 9.0 fps, although this is still pretty good by D-SLR standards.
The maximum image size is 6048x3400 pixels and, as per all the higher-end Nikon interchangeable lens cameras, there’s also two smaller sizes for both JPEG and RAW capture along with 8-bit RGB TIFFs. JPEGs can be captured at one of three compression levels and aspect ratios (including 16:9) plus there’s the option of using the smaller ‘DX’ format (i.e. ‘APS-C’) which has an imaging area of 16x24mm. The largest size RAW file can be captured with 14-bit or 12-bit RGB colour and there’s the choice of lossless compressed, compressed or uncompressed files at all three sizes.
As with the Z 7, the Z 6 has a single memory card slot for the XQD format which is a configuration that’s come in for some criticism, but there is some logic in Nikon’s thinking here.
For starters, XQD cards are super-fast – much faster than SDHC/XC UHS-II – so it makes the 12 fps shooting speed more useable in terms of how quickly the buffer memory fills and empties. There are obvious benefits when shooting 4K video and, in reality, any serious video-maker will be recording to an external device anyway and Nikon has allowed for simultaneous internal recording which will give you a back-up.
There’s also some element of future-proofing here too, because XQD still has plenty of scope for development in terms of data transfer rates. Additionally, the even faster CFexpress format – which uses the same form factor – will be supported via a firmware upgrade when it arrives.
That said, the downsides are that XQD cards are comparatively pricey and only made by a handful of manufacturers which is mainly why Nikon will be doing its own branding. The Z 6 is much more of a sports camera than the Z 7, but it creates smaller file sizes and so, for example, a 64 GB memory card will be able to store around 2500 JPEG/large/fine files with the optimisation on quality and up to 3500 with the emphasis on the uniformity of file size (which is then about 17 MB). And, besides, shouldn’t you always carry a spare card? Exactly.
The Z 6’s lower-resolution sensor means that this camera’s autofocusing system has fewer measuring points than the Z 7, although it still provides 90 percent coverage – both horizontally and vertically – and offers the same minimum sensitivity of -4.0 EV in the Low Light AF mode (at ISO 100 and f2.0).
The point count is 273 using a combination of phase-difference and contrast detection measurements, and the standard low-light sensitivity is actually slightly better than the Z 7’s at -2.0 EV (again at ISO 100 and f2.0). Switching between the single-shot and continuous modes is done manually (it only happens automatically when shooting in the movie mode) and there’s then a choice of five AF area modes in each. With single-shot AF you can adjust selectivity from Pinpoint to Wide-Area Large or there’s ‘Auto Area AF’ mode which uses the full array of points to detect the subject and focus on it.
With continuous AF operations, the ‘Auto Area’ mode also enables subject tracking, either with or without face recognition. There’s also a ‘Dynamic-area AF’ mode which, if the subject moves, automatically changes the focusing point to any of the surrounding ones.
The focus tracking can be fine-tuned over five settings from Quick to Delayed which varies the response to an interruption so the camera will either refocus immediately or stayed locked onto the subject… something you’d want to happen when, for example, panning.
A major benefit of the touchscreen is autofocusing by simply tapping on the subject (which also sets the tracking starting point in the ‘Auto Area AF’ mode) and there’s the option of auto shutter release instantly focus is achieved. However, as with the Z 7, you can’t move a focusing point by touch (you have to retap on the new position) and there’s no touchpad (or trackpad) AF option for focus point selection on the touchscreen when you’re using the EVF – which is a convenience feature found on many other mirrorless models these days. In practice, using the joystick-type controller adjacent to the camera’s thumbrest – so it’s easily reached – is probably just as quick. Nikon calls this control the ‘Sub-selector’ and it can also perform various navigational duties as well as serving as the AE and/or AF lock after being preconfigured in the Custom Setting Menu.
Being a mirrorless camera, the Z 6’s exposure metering is also sensor-based with the choice of multi-zone, centre-weighted average, fully averaged, highlight weighted or spot measurements. These drive the standard choice of ‘PASM’ exposure control modes with Nikon’s ‘Advanced Scene Recognition’ processing fine-tuning the auto settings to best match the subject and lighting situation. However, there are no standalone subject or scene modes. The overrides for the auto modes comprise the aforementioned AE lock, exposure compensation up to +/-5.0 EV and auto exposure bracketing with a choice of sequences for two, three, five, seven or nine frames.
As with the Z 7, the Z 6 does not have a built-in flash (and no PC sync socket either), but full compatibility with Nikon’s i-TTL auto flash exposure control and the ‘Creative Lighting System’ functions. Flash sync is again up to 1/200 second and there’s a flash auto bracketing function (plus the combination of bracketing for both available light and flash).
The focal plane shutter is supplemented by a sensor-based shutter with the option of combining the two for “electronic first curtain shutter” operation. The speed range of 30-1/8000 second remains unchanged irrespective of which shutter is used, but obviously the sensor shutter allows for silent and vibration-free shooting, but with the risk of rolling shutter distortion with moving objects (best seen in the ‘bent’ blades of an aircraft’s propeller or helicopter’s rotor). The hybrid shutter – which uses the sensor to make the exposure, but finishes with the FP’s second set of blades – still helps reduce vibration, but also makes it possible to use electronic flash.
The white balance control options start with a choice of three auto correction modes called ‘Keep White’, ‘Normal’ and ‘Keep Warm’. There are 13 presets for different types of lighting (including seven for gas-ignition sources) and up to six custom settings can be created.
Adjustments can be made via fine-tuning, auto bracketing or manual colour temperature control, settable over a range of 2500 to 10,000 degrees Kelvin, and auto bracketing. As on the Z 7, one of the presets is a new addition called ‘Natural Light Auto’ and is designed to reproduce colours “…closer to those seen by the naked eye” (whatever that may mean).
The Z 6 has eight ‘Picture Control’ presets which are supplemented by a further 20 ‘Creative Picture Control’ presets. The latter are essentially special effects, but with the same choice of adjustment parameters as the standard presets plus, additionally, ten effect levels… so the application can range from subtle to in-your-face.
All the ‘Picture Control’ presets have a revised set of adjustment parameters (compared to Nikon’s current D-SLRs), particularly in terms of sharpening. New is Mid-Range Sharpening which is added to the existing Sharpening and Clarity adjustments, and all three can now be adjusted collectively via a ‘Quick Sharp’ control which replaces the previous across-the-board ‘Quick Adjust’.
The Z 6 also has a multiple exposure facility (for up to ten shots with various exposure corrections) and an intervalometer which can record up to 9999 frames in a sequence. The self-timer is programmable for the delay countdown, number of shots and interval time.
On the corrective side, there’s the standard Nikon fare of ‘Active D-Lighting’ (ADL) processing to expand the dynamic range (with an auto bracketing function), noise processing for long exposures and high ISO settings and dual-shot HDR capture with either manual or automatic exposure adjustment and edge smoothing. There’s also a ‘Focus Shift Shooting’ function (first introduced on the D850) which can capture up to 300 frames, adjusting the focus in each via a predetermined step from one (narrow) to ten (wide). These frames can then be assembled post-camera for focus stacking. A handy ‘Peaking Stack Image’ function gives a monochrome preview image to show the areas in focus before all the frames are combined. Within focus shift it’s also possible to vary the interval time between shots, employ exposure smoothing or engage silent shooting.
The in-camera lens corrections now include ‘Diffraction Compensation’ to counter the softening that occurs when shooting at very small apertures. It joins the adjustable corrections for distortion and vignetting, but there are undoubtedly a whole lot of other things going on in the background too, such as minimising both lateral chromatic and spherical aberrations. The new Z mount has a total of 11 contact pins for increased communication between the camera body and the lens, further enhancing the scope for more sophisticated in-camera corrections. Physically, the fitting is a four-claw bayonet which gives increased strength and durability, but the big deal is the 55 mm inner diameter – versus 44 mm for the F mount – and the 16 mm flange-back distance. The significantly wider diameter will allow plenty of scope for faster lenses which Nikon is already exploiting with the 58mm f0.95 S Noct which is one of the first four Nikkor Z lenses now available, with another eight coming by 2020.
Nikon’s lens roadmap appears to imply another 11 lenses are in the planning stage and will be launched by the end of 2021. In the meantime, many Z camera owners will be relying on the FTZ mount adapter which maintains full AF and AE functionality with 90 current or recent-vintage Nikkor F mount lenses and will support – to varying degrees – a total of 360 models from the 1977 Ai (Automatic maximum aperture Indexing) mount update onwards. With the lens detached, the extra-wide lens mount dominates the front of the camera and that very short flange back distance (even shorter, incidentally, than that of the now-discontinued 1 Nikon mount) means that the sensor looks scarily exposed. As we noted with the Z 7, if you’re not careful, it’s actually quite easy to accidentally touch the sensor when detaching or fitting a lens… and this looked like it had happened with our test Z 7.
Canon’s solution with the EOS R is to automatically close the focal plane shutter when the camera is switched off and it’s something Nikon should think about implementing via a firmware upgrade. Thankfully, our test Z 6’s sensor was very much cleaner, but the risk is very real, especially if you are rushing a lens change.
The in-body image stabilisation uses sensor shifting to give five-axis correction (for yaw, pitch, roll, X and Y) for up to five stops of camera shake, depending on the lens focal length, which extends the possibilities for hand-held shooting in low light situations. The big benefit when using non-VR F mount lenses via the FTZ adapter is that they also gain three-axis image stabilisation. VR-equipped F mount lenses also gain three-axis correction, up from the previous two of the optical stabiliser alone.
In The Hand
Ergonomics have always been a Nikon strongpoint with many of its D-SLRs, especially the higher-end models, offering well-balanced handling and smoothly efficient control operations. The Z cameras go even further, making the most of the reductions in body size and weight without compromising comfort or controllability. Nikon has opted for a more conventional control layout – in other words, one similar to that of its D-SLRs – and this makes sense as a great many users will be making the big switch.
In terms of size and shape, the handgrip is virtually borrowed straight from the D-SLRs, including the control arrangement of shutter release with a surrounding power lever, and buttons for exposure compensation, ISO and video start/stop. We’ve already mentioned the joystick-type control on the rear panel and the rest of the layout here will also be familiar to users of Nikon D-SLRs. The electronic viewfinder will be a new experience, but Nikon has made sure it’s up to the job of convincing converts from the optical world by using a 1.27 cm OLED-type panel with a resolution of 3.686 megadots and a magnification of 0.8x. The refresh rate is 60 fps so there’s no discernible lag, and the display is adjustable for colour balance and brightness, the latter either automatically or manually over eleven levels. The definition is excellent as is the dynamic range, although the shadows can ‘block up’ in very contrasty conditions.
To make D-SLR defectors feel more at home, there’s the option of switching off any applied settings to give what Nikon describes as a “natural view” similar to that of an optical finder. The eyepiece is very comfortable to use and, as part of the Z 6’s weather protection measures, has a fluorine coating to help better repel moisture and grease. It also incorporates a proximity sensor for automatic switching between the EVF and monitor.
The latter is a nice, big 8.1 cm TFT LCD panel with a resolution of 2.1 megadots and is adjustable for tilt. It’s also adjustable for colour balance and brightness. In addition to AF functions already mentioned, the touchscreen implementation extends to the menus, a new customisable ‘i-menu’ display, and the replay/review functions. A top-deck info screen is retained – no doubt another nod to Nikon’s high-end D-SLR users – and is rather grandly dubbed ‘The Control Panel’. It’s a sharper-looking OLED panel rather than an LCD and adjustable for brightness, either manually or automatically.
The customisable ‘i-menu’ comprises 12 function tiles, each assignable from a range of just more than 30 functions. This is a refinement of the ‘Custom Settings Banks’ on some Nikon D-SLRs and very much easier to set-up or change. Better still, touch control makes the i-menu a very quick method of selecting and adjusting key functions without going near the conventional menus. The other customisation options include two multi-function ‘Fn’ keys adjacent to the lens mount and the multi-function control ring on the Nikkor Z lenses which can be set to manual aperture adjustment, setting exposure compensation, or as a full-time manual focus override.
The live view display – in both the viewfinder and the monitor screen –can be configured with basic capture settings, a real-time histogram, a dual-axis ‘Virtual Horizon’ level display and a 4x4 guide grid. You can cycle through most of these options using the ‘Display’ button which also accesses a monitor-based info screen. This includes the i-menu settings – which are selectable for adjustment, including by using the touchscreen – and is switchable between black-on-white and white-on-black displays.
The review/replay options include pages of four, nine or 72 thumbnails; zooming up to 32x and a slide show with adjustable frame intervals. Individual images can be displayed full-frame either with or without basic capture info or as thumbnails accompanied by a full set of histograms (i.e. brightness plus the RGB channels) or a highlight warning. Additionally, the autofocus points or area used to take the shot can also be shown. Cycling through the replay options also brings up various pages of detailed capture data which are displayed over the image. Borrowed straight from Nikon’s D-SLRs is a ‘Retouch Menu’ which provides a selection of in-camera editing functions including RAW-to-JPEG conversion, ‘D-Lighting’ (for dealing with contrast issues post-capture), Distortion Control, Perspective Control, Straighten, Resize and Image Overlay.
As is now common on mirrorless cameras, there’s both WiFi and Bluetooth LE wireless connectivity (a.k.a. Nikon’s ‘SnapBridge’), the latter providing the convenience of an always-on connection with easier pairing to smart devices for the speedy transfer of down-sized images. The SnapBridge app allows for the remote control of the camera via a smartphone.
Speed And Performance
Loaded with a Sony G series 64 GB XQD memory card – which, incidentally, has a writing speed of 400 MB/second and a reading speed of 440 MB/second – the Z 6 captured 44 best-quality JPEGs in 3.655 seconds which represents a shooting speed of 12.0 fps on the dot. The test files averaged 12.5 MB in size.
While it uses fewer measuring points, the Z 6’s autofocusing doesn’t seem to lack anything in terms of speed or accuracy compared to the Z 7. In fact, subjectively, it seems even more responsive, ensuring more reliable tracking virtually across the entire frame, even when the subject is moving erratically or unpredictably. Nikon’s ‘3D Tracking AF’ in the likes of the D850 is still king here, but the Z cameras aren’t very far behind and actually ahead of some of their mirrorless rivals.
The exposure metering also proves to be very reliable even in contrasty situations, with some emphasis on maintaining as much detail in the highlights without compromising the shadows. The dynamic range is very good, allowing for plenty of exposure latitude when shooting at the lower sensitivity settings. In fact, even at the higher ISO settings, there’s still plenty of scope for brightening the shadows post-camera.
With far fewer pixels to work with, we weren’t expecting the Z 6’s image quality to match the Z 7 for the sheer richness of the detailing and the seamlessly smooth tonal gradations, but it still does an excellent job with both. The best-quality JPEGs are crisp and punchy with excellent colour fidelity across the spectrum and the usual well-judged Nikon balance of saturation and realism. Of course, the refined ‘Picture Control’ presets allow for much tweaking of sharpness, contrast saturation and hue to suit personal preferences.
The noise reduction processing is very well managed so excellent detailing, colour saturation and contrast are maintained up to ISO 6400 and with only a small reduction in the overall image quality at ISO 12,800 and even at ISO 25,600. The ISO 51,200 setting is still quite useable and, while both detailing and saturation start to suffer, the visible noise is still quite fine-grained.
The camera’s low-light shooting capabilities are, of course, enhanced by the in-body image stabiliser, and even more so when the faster Nikkor Z lenses are used, such as the 35mm f1.8 and 50mm f1.8 primes (plus, of course, the super-fast f0.95 58mm which we’ve yet to sample). Importantly too, you still have autofocusing down to -4.0 EV, although there is a built-in LED illuminator for low-light AF assist too.
While, not surprisingly, the Z 6 and Z 7 share a lot when it comes to video recording, there are some key differences. The most important of them is that the Z 6 records with a full pixel read-out (i.e. no pixel binning) from across the full sensor width at 6K resolution before downsampling to 4K for enhanced image quality (similar to Sony’s A7 III). This means lens focal lengths remain the same and the image quality, particularly sharpness and definition, are exceptional.
The 4K clips are recorded in the Ultra HD resolution of 3840x2160 pixels at either 25 fps (PAL standard) or 24 fps with MPEG-4 AVC/H .264 compression in either the MOV or MP4 formats. The Full HD (1920x1080 pixels) frame rates run up to 100 fps (or 120 fps in NTSC) to create slow-motion effects (up to 24 fps x5). Time-lapse movie sequences can be captured in-camera in only 2K res (4K requires post-camera processing of the frames).
On the audio side, the Z 6 has built-in stereo microphones with manually adjustable levels and an attenuator, and these are supplemented by both a stereo audio input and output (both 3.5mm minijacks). The sensitivity range for shooting video is 100 to 51,200 (and extendable to ISO 204,800). The maximum recording duration is the 29 minutes and 59 seconds imposed by the EU tax legislation on video cameras (but by-passed if you use an external recorder).
Videography features include zebra patterns, an N-Log gamma profile (to optimise dynamic range), a focus-peaking display, embedded time coding, and hybrid IBIS and electronic image stabilisation. The native N-Log recording is only available via the HDMI output which delivers 10-bit 4:2:2 colour and a claimed dynamic range of 12 stops. A useful ‘View assist’ function displays gradation compensation while recording with N-Log for confirmation of the final look of the footage.
Simultaneous recording to the memory card isn’t possible with the 10-bit streaming, but simultaneous recording is possible with 8-bit 4K UHD recording (2K to the memory card). Like the Z 7, the Z 6 also supports the Atomos Open Standard protocol for HDMI triggering and timecode while, in turn, the new Atomos Ninja V recorder/monitor will support the 10-bit 4K N-log output from both Nikon’s Z series cameras. As it happens, the XQD card would have been up to handling internal N-Log recording too, but the Flat ‘Picture Control’ is available with 8-bit 4:2:0 colour and still delivers an easily gradable image.
The video functionality is extensive and includes continuous AF with subject tracking (using slightly fewer points due to the 16:9 crop) and the options to adjust both the speed and tracking sensitivity. All the ‘PASM’ exposure modes are available along with the ‘Picture Control’ and ‘Creative Picture Control’ presets, the ‘Movie Active D-Lighting’ processing and exposure compensation. The latter can be applied very smoothly via the multi-function control ring which is a feature of all the Nikkor Z lenses. It can also be used to manually adjust focus, but it’s obviously a fly-by-wire control.
It’s again pretty obvious that the Z 6 is primarily targeted at existing Nikon D-SLR users, but its combination of performance, features and price means it also comes into play for anybody ready to make the switch to mirrorless or, indeed, to a full-35mm sensor. So, if you’re looking at the Fujifilm X-H1, Panasonic Lumix GH5 or G9, Sony A7 III, Leica CL or even the Canon EOS R, then the Z 6 has to be in the mix too. As with the EOS R, the choice of lenses is still small compared to these other models, but you probably aren’t buying a whole system in one hit anyway. And while the Z 6 definitely has strong Nikon genes, the excellent ergonomics and user interface easily transcend any brand-related traits. It’s simply one of the best-handling interchangeable lens cameras on the market (along with the Z 7, of course), making good use of external controls, menus and a touchscreen... applicable in any combination you prefer.
The combination of image quality and shooting speed also make the Z 6 highly competitive, with the benefits of the full-35mm sensor with bigger pixels manifested in the dynamic range and high-ISO performance. Throw in the excellent EVF, the reliable autofocusing and what we’ve seen so far of the Nikkor Z lenses, and the Z 6 adds up to a truly formidable package, making it the all-rounder of the all-rounders.