SONY A7S III
The third-gen A7S is primarily pitched at pro-level video-makers, but what makes it so capable in this application also makes it a rather special stills camera too.
By making its third-generation A7S the purist’s hybrid video camera, Sony has also made it the purist’s still camera. Don’t worry about the 12 megapixels res – it’s enough for many applications – but check out the dynamic range and the low-light performance, which is nothing short of epic.
What exactly is a hybrid mirrorless camera? You’d think it was a model that appeals equally to photographers and video-makers by virtue of its feature set and performance with both of these applications. Strictly speaking then, by this definition, only a small number of models would qualify as truly hybrid, as most are more photographic in design and a few are more video-orientated, the most notable of the latter being Panasonic’s Lumix S1H and GH5/ GH5S, and Sony’s A7S line.
In reality though, really every mirrorless camera is a highly capable stills camera and it’s essentially just the video functionality that varies. So while the latest-generation A7S III is designed to wow video-makers with its massive suite of pro-level features and specifications, it also offers plenty of attractions for still photographers… in fact, it’s right up there with the best of them in terms of its photographic image quality. Of course, there’s the question of why you’d spend all that money – around $1,000 more than the A7R IV and twice the price of the A7 III – if you weren’t going to put this camera’s significant video capabilities to good use but, ironically, the A7S
III has certain appeal for the purist photographer. The sensor that makes it work so well as a video camera, is equally beneficial for
still photography too.
It’s an all-new backsideilluminated (BSI) full frame Exmor R CMOS with an effective pixel count of 12.1MP, a number that may cause you to raise an eyebrow, but here’s the proof that less can be more when it comes to pixel counts. The total pixel count is 12.9 million, which gives a pixel size of 8.36 microns – essentially medium format camera territory. Bigger pixels mean a higher signalto-noise ratio which, in turn, means a wider dynamic range – 14 stops for stills in this instance – and increased sensitivity. The native range is equivalent to ISO 80 to 204,800 which is expandable to ISO 40 and 409,600 so the A7S III is a pretty impressive performer in low-light situations. And, in real world terms, 12 megapixels resolution is sufficient for a wide variety of applications as anybody who has owned a Nikon D3 or D700 will tell you (this writer included). To this you can add 10-bit HEIF capture, 10fps continuous shooting with AF/AE adjustment, 759 point autofocusing with lowlight sensitivity down to EV -6.0 (ISO 100 and f/2.0), a big EVF with a resolution of 9.44 million dots and a magnification of 0.9x, a fullyarticulated LCD screen (actually a first on a Sony A7-series body) and the option of using super-fast CFexpress Type A memory cards while retaining compatibility with the popular SD format. There’s plenty more, of course, but how’s that for the basis of a very appealing stills camera?
ON THE CARDS
The A7S III is the first camera to use the more compact Type A CFexpress card, which is quite a bit smaller than Type B (and even a bit smaller than SD), but is capable of a read speed of up to 800 MB/second and a write speed of up to 700 MB/second… so they’re over twice as fast as the speediest UHS-II SD card. Consequently, Sony says burst lengths of over 1,000 frames are possible with RAW capture (thanks also to a bigger buffer memory), and it also allows for 4K UHD video recording in-camera at 120fps with 10-bit 4:2:2 colour (for the full video rundown go to the Making Movies panel). The size difference with SD requires a dual-format arrangement for the card slot – Sony calls it a “multi slot” – and there are two of these so you can mix and match cards as well as set up either backup or relay recording, or assign a file type to a specific card. While the multi slot will actually accept two cards at the same time, they can’t be used together. Needless to note, however, the SD card slots are compatible with UHS-II speed devices. Sony currently offers 80 or 160GB capacity versions which are, at this point, all that’s available. You’re looking at around $300 for the 80GB card and $680 (ouch) for the 160GB device.
The maximum image size is 4240x2832 pixels and JPEGs can be recorded at two smaller sizes with a choice of three compression settings and four aspect ratios of 3:2, 4:3, 16:9 and 1:1. The same selection of capture settings is available for HEIF capture, while RAW files can be captured either uncompressed or lossy compressed. Sony joins Canon in offering the 10-bit HEIF alternative to 8-bit JPEGs, and it’s essentially the still derivative of the more efficient HEVC H.265 video codec. The initials stand for High Efficiency Image Format and it delivers both a wider dynamic range and a wider colour gamut without increasing the file size. In fact, twice as much information can be saved in an HEIF file as in a JPEG file of the same size. It creates much more natural HDR stills than the artificial-looking simulation processing of JPEGs. The A7S III offers the option of recording HEIFs with either 10-bit 4:2:2 colour sampling or 10-bit 4:2:0. In-camera HEIF-to-JPEG conversion is available – even these JPEGs will have a wider dynamic range – as is RAW+HEIF capture.
The sensor is mated with a new and faster Bionz XR processor that, Sony says, is eight times more powerful than the previous generation Bionz X, three times zippier than the previous X version and also reduces rolling shutter distortion by a factor of three over the A7S II. The maximum continuous shooting speed of
10fps is available when using either the mechanical or electronic shutter, and you get real-time live view with the latter at up to 8fps, again with full AF/AE adjustment. In reality, you’re very unlikely to ever challenge the 1000+ frames burst length, which applies to RAWs (either compressed or uncompressed), and maximumquality JPEGs or HEIFs when using a CFexpress Type A memory card.
THE A7 SERIES CAMERAS HAVE
PUT ON A BIT OF WEIGHT SINCE THE FIRST GENERATION MODELS, BUT THEY’RE STILL AMONG THE MOST COMPACT FULL FRAME MIRRORLESS BODIES ON THE MARKET.
With a UHS-II speed SDXC card, the burst lengths are reduced, but are still very generous.
GET THE LOOK
In-body image stabilisation is provided via sensor shifting which, in co-operation with lens-based optical image stabilisation, operates over five axes and gives up to 5.5 stops of correction for camera shake. This obviously helps make the most of the camera’s inherent low-light shooting capabilities. Interestingly here though, Sony hasn’t taken the opportunity to use sensor shifting to give a higher resolution image via multi-shot capture with in-camera merging. This would have been a bit of extra icing on the cake for stills shooters, but it
perhaps shows where Sony’s main priorities lie with the A7S III.
You see this with the camera’s set of Creative Look picture presets rather than the ‘Creative Styles’ that photographers will be more familiar with. The Creative Look presets have been borrowed from Sony’s much-lauded Venice 6K pro cinema camera and have double initials as designations rather than descriptors such as Standard, Portrait or Vivid. You can pretty well work out what stands for what with most of them – ‘ST’ is Standard, ‘PT’ is Portrait, ‘NT’ is natural, ‘VV’ is vivid, ‘VV2’ is also vivid with brighter tones, ‘BW’ is B&W and ‘SE’ is Sepia. However, ‘FL’, ‘IN’ and ‘SH’ – which, incidentally, are all new – may have you scratching your head. ‘FL’ stands for Film
Like, and is described as creating a “moody finish”. ‘IN’ represents Instant (camera) and gives “matte textures” by reducing contrast and saturation. ‘SH’ stands for
Soft & High Key and is designed to produce an image that has a “bright, transparent, soft, and vivid mood”. Got it? The Creative Looks have adjustable parameters for contrast, highlights, shadows, fade, saturation, sharpness, sharpness range, and clarity. All are set via numerical value ranges. Alternatively, you can create up to six custom ‘Looks’. Of course, everything can be previewed in the excellent high-res EVF. There are no built-in special effects.
Noise reduction is provided for both long exposures and high ISO settings, plus Sony’s long-standing Dynamic Range Optimiser (DRO) processing is retained, but there’s no multi-shot HDR mode probably because of the availability of 10bit HEIF and HLG (Hybrid Log Gamma) Still Image capture.
The DRO options comprise auto correction – based on the contrast range of the scene – or five levels of preset correction. An auto bracketing mode is available for dynamic range expansion processing, as well as for white balance and exposure. In-camera lens corrections are provided for vignetting (i.e. brightness falloff), chromatic aberrations and distortion. The A7S III has flicker detection and correction for more stable exposure control when using continuous shooting under gas-ignition light sources (i.e. fluoro types) which, for example, are common in indoor sporting venues. These actually switch on and off continuously, but at such a high frequency that it’s largely imperceptible to the human eye, but can make quite a difference to exposures and colour balance, so the anti-flicker function adjusts the shutter’s timings very fractionally during a continuous sequence to avoid this.
There’s an intervalometer that’s programmable for up to 9,999 shots and includes an adjustment for AF tracking sensitivity. No multiple exposure facility though.
STAYING ON TRACK
With the new sensor comes a new version of Sony’s Fast Hybrid autofocusing system that employs 759 phase-difference detection points and 425 contrast-detection points, giving 92% frame coverage. Low-light sensitivity extends down to EV -6.0 at ISO
100 and f/2.0. AI-based subject recognition drives the camera’s Real Time Tracking based on colour, pattern, distance, and face and eye data. Additionally, the Real Time Eye AF can be switched between humans and animals, with the option of auto or manual right/ left eye selection with the former. Sony says performance has been improved by 30% and it’s able to keep tracking even if the subject looks away or there’s an interruption caused by another object passing in front. Moreover, tracking sensitivity can be varied over five levels from ‘Locked On’ to ‘Responsive’. There’s also the choice of focus or speed priority
(or a balance of both), set independently for single-shot and continuous modes. Switching between the single-shot and continuous modes can be done manually or left to the camera when it’s set to AF-A. Similar to the A9 II, there’s an ‘Aperture Drive in AF’ which has the option of selecting focus-priority or silentpriority; the former maintains an open aperture during autofocusing in order not to degrade the viewfinder image. Normally, you wouldn’t notice anything, but with the A7S III’s no-blackout EVF operated at 8fps, the lens continually stopping down would create annoying flickering.
There’s a choice of five area settings, namely Wide, Zone, Centre Fix, Spot and Expand
Spot. All five are also available with tracking. In the Spot modes, the focusing zone to be set to one of three sizes – small, medium or large – to finetune selectivity. In the Expand modes, the surrounding points are automatically selected if the subject subsequently moves. Continuous AF is supplemented by a Lock-On function that works with any of the area modes to provide more reliable tracking. A focus point or area can be registered for instant recall, which is useful when shooting the same scene or subject on a regular basis. Additionally, it can be set to switch position automatically when the camera is turned to the vertical position. The AF frame can be switched between white or red to enhance visibility. The A7S III also has the ‘Circulation Of Focus Point’ function introduced with the A9 II that enables the focus area to be rotated through the upper, lower, left, and right edges of the frame, primarily designed for situations where a subject often moves through the frame. A number of autofocusing functions are available via the rear screen’s touchscreen, including the selection or moving of a focusing point/zone, with a ‘Touchpad’ option that allows this to be done when using the EVF (with the choice of absolute or relative positioning on-screen). Additionally, Touch Tracking allows you tap on a subject to start the process.
The manual focus assists comprise a magnified view and a focus peaking display that can be set to red, blue, yellow or white and high, mid or low intensity.
The focus magnifier can be set to operate continuously or for timed durations of two or five seconds. It’s also available with autofocusing to help confirm focus.
The exposure control options are standard Sony A-series fare, and based on 1200-point on-sensor metering with the choice of multizone, centre-weighted average, fully averaged, highlight-biased or spot measurements. The spot meter’s size can be switched between standard or large, and either locked to the frame’s centre or linked to the active focus point(s). The multi-zone metering can be set to face-priority. The auto exposure control mode overrides comprise an AE lock, exposure compensation of up to +/-5.0 EV (although the dial is only marked to +/-3.0 EV, so going further requires a trip to the relevant menu) and auto bracketing over sequences of three, five or nine frames. The standard set of ‘PASM’ exposures modes is supplemented by a fullyautomatic mode that provides subject/scene analysis and adjust the capture settings accordingly.
The mechanical shutter has a speed range of 30-1/8000 second with flash sync up to
1/250 second, and there’s the
option of an electronic shutter for silent and vibration-free shooting (with the same speed range). There’s also the hybrid electronic front curtain shutter which starts the exposure with the sensor shutter and finishes it with the conventional shutter. This provides some reduction in vibrations and noise while still allowing the use of electronic flash.
The auto white balance control offers the choice of three modes – Standard, White-Priority or Ambience-Priority. Alternatively, there are a total of 10 presets – including four for different types of fluoro lighting and one for shooting underwater – with fine-tuning over the blue-to-amber and green-tomagenta colour ranges. Manual colour temperature setting is available over a range of 2,500 to 9,900 Kelvin. Up to three custom white balance settings can be created and, as noted earlier, white balance bracketing is available over a sequence of three frames.
IN THE HAND
The A7-series has put on a bit of weight since the first-gen models, but they’re still among the most compact full-framers on the market. The A7S III’s size and style are very similar to that of the A7R IV and A7 III, with a good-sized handgrip and a matte black finish.
The body is magnesium alloy with upgraded weather sealing and, as you’d expect for a prolevel camera, the A7S III feels very solidly built. The control layout centres on a main mode dial with front and rear input wheels, a rear panel navigator wheel (which incorporates a fourway keypad) and joystick control that Sony calls a “multi-selector”. There’s a dedicated dial for setting exposure compensation (which is lockable), and the video start/ stop button has been moved to the top panel, located just behind the shutter release, which is much more convenient. The customisation options include four multi-functional ‘C’ buttons, the rear control wheel and its keypad quadrants, and the onscreen Function Menu comprising 12 tiles to give direct access to the assigned items. There are dedicated Function Menus for photography and video, while the customisable controls have three setups for photography, video and playback. Additionally, there’s My Dials customisation for the input and control wheels. There is, of course, a customisable My Menu, and up to four banks of camera setups – designated M1 to M4 – can be created and three of them assigned to the 1, 2 and 3 positions on the main mode dial.
The A7S III introduces a completely new menu design that employs progressive clickright navigation to take you from chapter to page to sub-menu and settings. The chapters use colour-coded tabs, with the same colour used for the page numbers, making it much easier to see where you’re going or want to go. It’s more logically organised and, consequently, a huge improvement over the previous setup. Going hand-in-hand with this is the full implementation of touchscreen controls to also include the main menus, the Function Menus and the monitor’s control panel display.
Another first for the A7 line is a fully articulating display, which is obviously a big plus for video users who often have more need for a wider range of adjustments. The panel itself is a 3-inch TFT
LCD with a resolution of 1.44 million dots and adjustable for brightness. As noted at the start of this review, the EVF steps up to 0.6inch (1.6cm) OLED panel with an impressive 9.44 million dots resolution and 0.9x magnification, making it easily the best-looking electronic viewfinder we’ve seen to date, and the most comfortable to use. It’s adjustable for both brightness and colour balance.
The live view screen can be configured with a guide grid (selected from a choice of three), and a zebra pattern to indicate areas of overexposure (with adjustable levels set between 70 and 100+), plus you can cycle between a real-time histogram and a dual-axis level indicator.
The battery is Sony’s highcapacity, 2,280mAh NP-FZ100 lithium-ion pack which gives a claimed shot count of 600 when using only the rear display and
510 with the EVF. The A7S III is compatible with the VG-C4EM battery grip (as also used by the A9II and A7R IV) that holds two NP-FZ100 packs and essentially doubles the range, plus the batteries can be recharged insitu via the camera’s Type C
USB connection. The USB-C connection also supports tethered shooting. The other interfaces are HDMI Type A (i.e. full size), microUSB 2.0, and 3.5mm audio (in and out) minijacks. The wireless connections are Wi-Fi with NFC (supporting both the 2.4 and 5.0GHz bandwidths) and
Bluetooth LE.
SPEED AND PERFORMANCE
Using a Sony 80GB CFexpress Type A memory card and the mechanical shutter, the A7S III captured a burst of 105 JPEG/large/ extra-fine files in 10.525 seconds, representing a shooting speed of 9.97fps, which is obviously as close to 10fps as makes no difference. Out of interest, we also ran a time trial using a Panasonic 64GB SDXC UHS-II V90 speed card, and a sequence of 64 bestquality JPEGs was recorded in 6.455 seconds – that’s a shooting speed of 9.91fps. So you don’t lose any speed with the fastest SD cards, but the burst lengths are reduced. The test files averaged 8.75MB in size.
Sony’s continued development of its Fast Hybrid autofocusing puts it on par with the best that’s available in mirrorless cameras. Canon’s Dual Pixel CMOS AF II has set the standard, but Sony is mounting a serious challenge and you’d have to say the A7S
III’s tracking performance – which in unerringly accurate in any situation when using face/eye detection – is on par with what we’ve experienced in the EOS R5 and R6. Even fast or erraticallymoving subjects are kept in sharp focus no matter how much the speed or direction change, so sports and action photography would definitely be a potential application… especially since it’s all still working brilliantly at 10fps. And the low-light performance is superlative too, so this camera still autofocuses reliably in situations where the human is starting to struggle to discern details.
The imaging performance is equally impressive and there’s certainly a tonality – related to the big pixel size – that’s very appealing visually. The best-quality JPEGs look superb in terms of the
WHILE THE ‘CREATIVE LOOKS’ AND THE ‘PICTURE PROFILES’ ARE MAINLY CINEMATIC IN EMPHASIS, THERE’S SOME GREAT OPTIONS HERE TO EXPLORE WITH STILL PHOTOGRAPHY.”
colour reproduction, contrast and gradation… and it’s hard to fault either the detailing or definition. There will be a limit to how large these files can be reproduced, but it’s unlikely to be an issue unless you’re thinking of making exhibition prints, and even then we suspect everything would hold together pretty well. The wide dynamic range translates into huge exposure latitude so, with RAW files, there’s up to four stops of get-out-of-jail exposure correction, the shadows easily being brightened without any discernible noise. In practical terms, this means you can happily underexpose in the camera to keep tonality in even the brightest highlights. While the Creative Looks – and also the Picture Profiles – are mainly cinematic in emphasis, there’s some great options to explore with still photography and experiment with tonality, saturation and contrast.
The really big deal with the
A7S III, however, is its high ISO performance and here it’s without peer in either mirrorless cameras or DSLRs. There’s been some conjecture that the sensor might have dual-gain circuitry because the noise levels actually appear to drop at around ISO 16,000 and beyond, but it’s hard to see Sony having any sound reasons not to admit to it if this was indeed the case. We tend to think it’s something to do with how the noise reduction algorithms are being tweaked when there’s already such a high signal-to-noise ratio. Regardless, the A7S III looks just as good at ISO 12,800 as it does at ISO 400, and there’s a minimal loss of either definition or saturation all the way to ISO 51,200. Grain starts to manifest itself at ISO 102,400 and there’s a noticeable softening of finer details, but these are still useable images provided you don’t want to make big prints. With the IBIS and an ultra-fast prime – of which there are now plenty for the FE mount – you’ll never need to be afraid of the dark.
THE VERDICT
On paper, there’s no question that the A7S III is a video camera first and a stills camera second, but in practice it’s actually a pretty awesome stills camera. The resolution simply won’t be an issue for a great many users, but the resulting image quality in terms of dynamic range, signal-to-noise and the high ISO performance are the major plusses. It’s simply unmatched in terms of its low-light capabilities, making it a brilliant camera for street photography. Moreover, many of those cinematic profiles and looks actually work really effectively with stills, particularly if you like more muted colours.
Yes, you’re paying more for less in terms of resolution, but the A7S III’s still imaging performance is just so comprehensively good and its supreme low-light capabilities give such unsurpassed flexibility, it’s undoubtedly the discerning photographer’s hybrid mirrorless camera. Of course, it also happens to be the discerning video-maker’s hybrid mirrorless camera too, so you really can’t lose.