On Trial: Sony A7 Iii
Sony’s quest for domination of the interchangeable lens camera business continues with its latest A7 series generational upgrade. The Mark III version of the ‘entry-level’ A7 model betters its predecessor in just about every way.
The third-gen version of Sony’s A7 full-35mm format mirrorless camera offers an appealing combination of performance, speed and affordability – a benchmark for whatever Nikon and Canon may be cooking up for this category.
It’s an indication of how well executed Sony’s A series full-35mm mirrorless cameras were right from the start that all the original models are still available close to five years after their launch and now after third-generation upgrades for the original A7 and A7R. This has enabled Sony to market a wider range of bodies (numbering nine right now) with an entry-level price now at $1499 which is a lot cheaper than anything in the D-SLR world (except for Sony’s own A77 II). It’s all about making converts and, once you’re committed, you’re very unlikely to go anywhere else except upwards through the FE mount system.
If you’re already an A7 user who skipped the Mark II upgrade, you’re probably about ready for the A7 III, but this model is also tasked with continuing to lure enthusiast-level users away from their D-SLRs. As with all the A7 models and the A9, the big deal is the smallness of the bodies despite housing a full-35mm sensor. From among the full-35mm D-SLRs, only Nikon’s D750 gets close and it’s still nowhere near as petite as even the slightly more bulked-up Mark III cameras. Of course, it’s pretty much all academic when it comes to the lenses because the 35mm imaging circle is the same irrespective of the camera configuration, but you’re still ahead with the more compact mirrorless bodies. After you’ve been using one for a while, it’s surprising just how bulky a D-SLR feels in comparison.
The A7 III is designed to make such comparisons even more revealing as the third-generation upgrades include a new sensor, processor, electronic viewfinder and autofocusing system plus a much faster continuous shooting speed, in-body image stabilisatio and, of course, 4K video recording.
The styling is virtually identical to that of the A7R III and the A9 which is a little more purpose fullooking than the earlier models thanks to the matte black finish and bigger handgrip. The new bodyshell comprises magnesium alloy covers and chassis with weather sealing to protect against dust and moisture. The LCD monitor screen is adjustable for tilt and has some touch controls (mostly related to autofocusing) while the EVF is a 1.3 cm OLED-type panel with a resolution of 2.359 megadots and a magnification of 0.78x (35mm equivalent). The control layout continues to be based around a main mode dial with front and rear input wheels, a second dial for applying exposure compensation, a navigator wheel/keypad and various function buttons (a number customisable). As on the A7R III and A9, a joystick-type toggle control (which Sony calls the “Multi-Selector”) has been added primarily to allow for the easier and quicker selection of AF points (now that there’s a great deal more of them), but which can also be used for various navigational duties.
The battery is the same highercapacity NP-FZ100 2280 mAh ‘InfoLithium’ pack that’s used in the A7R III and A9 and extends the shooting range to around 710 shots. It can be recharged in-camera via the USB port and the A7 III is also compatible with the optional VG-C3EM battery grip which accommodates two NPFZ100 packs.
There are now dual memory card slots with a proper latched cover for the compartment. One slot is exclusive to the SD format and the other compatible with both SD and Memory Stick Duo devices. As on the A7R III, only the former is UHS-II speed compatible while the latter is restricted to UHS-I. The file management options are simultaneous recording to both cards (either stills or video clips), split JPEG and RAW or split stills and movie clips, copying and automatic overflow. The A7 III has Sony’s ‘Multi Interface’ hotshoe – which is designed to accept various other accessories besides a flash unit – but unlike the A7R III, it doesn’t have a PC terminal for flash sync. The rest of the interfaces are the same though, and comprise both micro USB 2.0 and Type C USB 3.1 Gen. 1 ports (the latter also enabling tethered operations) and both a stereo audio input and an output (3.5 mm minijacks for each). Wireless connectivity is via WiFi with NFC and Bluetooth LE.
ON THE INSIDE
The inside story starts with an all-new, 25.3 megapixels version of Sony’s ‘Exmor R’ BSI (backside illuminated) CMOS sensor which has an imaging area of 23.8x35.6 mm and a sensitivity range equivalent to ISO 100-51,200 (expandable to either ISO 50 or 204,800). The effective pixel count is 24.2 million which gives a maximum image size of 6000x4000 pixels. JPEGs can be captured in one of three image sizes and three compression settings at either the 3:2 and 16:9 aspect ratios. RAW files are captured with 14-bit RGB colour and either compressed or uncompressed. RAW+JPEG capture can be with any configuration of JPEG size and quality. The camera will also automatically crop to the ‘APS-C’ format if an E mount lens is fitted. By the way, this sensor retains an optical low-pass filter - although it’s comparatively weak - to balance optimum resolution with some filtering for moiré patterns (but only horizontal).
It’s mated with both a new front-end LSI processor and an updated version of Sony’s ‘Bionz X’ main processor, both of which contribute to a significant increase in shooting speed thanks a faster data read-out and subsequent processing. This enables continuous shooting at up to 10 fps with frame-by-frame adjustment of the autofocusing and exposure (and with either the focal plane shutter or the camera’s sensorbased silent shutter). And yes, 14-bit RAW capture is possible at 10 fps. Better still, continuous live view framing (i.e. with no blackouts between frames) is available with only a small reduction in the shooting speed to 8.0 fps. Burst depths are quoted as 163 frames for JPEG/large/extra-fine capture, 89 compressed RAW files or 40 uncompressed RAW files. All are big increases over the previous two versions of the A7.
The new LSI also delivers a big improvement to the sensor’s signal-to-noise so Sony is again quoting a very wide dynamic range of 15 stops at the lower ISO settings. This is one benefit of the sensor’s ‘Dual Gain’ design which gives two base ISO values – one at ISO 100 to optimise the dynamic range when shooting in brighter conditions and the other at ISO 640 to reduce noise when shooting in low-light situations.
INTERESTINGLY, THE A7 III HAS SONY’S MOST SOPHISTICATED HYBRID AUTOFOCUSING SYSTEM YET – WITH A MASSIVE 693 PHASEDIFFERENCE DETECTION POINTS GIVING 93 PERCENT FRAME COVERAGE.
In a nutshell, at ISO 640 or higher, amplification of each pixel’s output (which is how the high ISO settings work) is performed on the sensor, ensuring a very low level of noise at the read-out stage.
The addition of in-body image stabilisation via sensor-shifting is a big plus given the rapidlyexpanding number of non-Sony FE mount lenses becoming available, many without optical image stabilisation. The A7 III’s IBIS provides five-axis correction and up to 5.0 stops of shutter speed compensation when shooting hand-held.
In The Frame
Interestingly, the A7 III has Sony’s most sophisticated hybrid autofocusing system yet – combining the 693 phase-difference detection points from the A9 and the 425 contrast-detection points from the A7R III. The PDD points provide a massive 93 percent frame coverage which means better tracking performance as well as being able to lock on to subjects located right at the very edges of image.
The faster processor also enhances the tracking reliability, including in low-light situations, and delivers shorter response times with better accuracy than before. In fact, sufficiently so as to allow for the advanced ‘Eye AF’ function which locks onto a subject’s eye for subsequent tracking which is then maintained even if the subject then looks away or the face is partially hidden for a few moments. Low light sensitivity extends down to -3.0 EV (at ISO 100 and f2.0) and there’s a built-in LED illuminator for low light/contrast assist. Switching between the single-shot and continuous AF modes can be done manually or left to the camera when it’s set to ‘AF-A’.
Autofocus point selection can also be performed manually or automatically, the former via one of five area modes called Wide, Zone, Centre, Flexible Spot and Expand Flexible Spot. The Flexible Spot options allow the focusing zone to be adjusted to one of three sizes – small, medium or large – to better suit the subject matter. In the Expand mode, the surrounding points are automatically selected if the subject starts to move. Continuous AF is supplemented by a ‘LockOn’ function which 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 face detection AF allows for both face recognition and left/right eye detection.
As on the A7R III, there’s a total of four pages devoted to AF set-up and functions (plus yet another page devoted to the various assists), and these include finetuning for the tracking sensitivity with a choice of five settings from ‘Locked On’ to ‘Responsive’. Additionally, the single-shot and continuous modes can be prioritised for either achieving focus or enabling shutter release, or a balance of both.
Manual focus assist is provided by a magnified view (up to 5.9x) and a focus peaking display which can be set to red, yellow or white with three levels of sensitivity (high, mid or low). The focus magnifier can be set to operate continuously or for preset timed durations of either two or five seconds. It’s also available to assist with determining sharpness when using autofocusing.
Autofocusing performance used to be a key D-SLR advantage, but in various ways the latestgeneration mirrorless cameras – and especially the new Sony Alpha models – have moved ahead both in speed and accuracy. We crowned the A9 as the king of the ILC autofocusing systems, but the A7 III is actually better again and so puts an end to that short reign.
Lighting the Way
Exposure control is based on on-sensor metering with 1200 measuring points and the choice of multi-segment, centre-weighted average, fully averaged, highlightbiased 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 or zone.
The standard selection of ‘PASM’ exposure control modes is supplemented by a full-auto mode which performs subject/scene analysis to fine-tune the exposure settings. Unlike the A7R III though, the A7 III also has a set of manually-selected subject modes for Portrait, Sports Action, Macro, Landscape, Sunset, Night Scene and Night Portrait.
The overrides for the auto exposure control modes comprise an AE lock (which now has a dedicated button), exposure compensation of up to +/-5.0 EV (although, again, the dial is only marked to +/-3.0 EV with the additional range accessed in the ‘Exposure 1’ menu) and auto exposure bracketing over sequences of three, five or nine frames. For the first two, the maximum adjustment per frame is +/-3.0 EV while over nine frames, it’s +/-1.0 EV. Exposure bracketing sequences can be combined with the self-timer.
As noted earlier, the camera’s focal plane (FP) shutter is supplemented by a sensor-based shutter which Sony only utilises
WHILE 24 MP MAY NOT LOOK AS GLAMOROUS AS 42 MP, AS WE’VE SAID ON A NUMBER OF OCCASIONS, IT’S NOT SO MUCH ABOUT HOW MANY MEGAPIXELS AS WHAT YOU DO WITH THEM.
for either silent shooting or ‘electronic front curtain’ operation to minimise vibrations (while still allowing for flash photography). The shutter speed range is 301/8000 second with flash sync up to 1/250 second and a ‘B’ setting for longer exposure durations. Like its ‘R’ sibling, the A7 III gains flicker detection and automatic reduction for more even exposures when using continuous shooting under gas-ignition (i.e. fluoro) light sources. These actually switch on and off continuously, but at the mains power frequency of 50 Hz it’s largely imperceptible to the human eye. However, between the bright ‘peaks’ it can make quite a difference to both exposure and colour balance so the anti-flicker function adjusts the shutter’s timings very fractionally during a continuous sequence to avoid this. It does slow the camera down, but not by much, and is obviously a pretty handy facility to have when shooting, for example, indoor sports.
Also handy is the option of tweaking the automatic white balance correction which can be set to Standard, White-Priority or Ambience-Priority. There are ten lighting presets – including for four different fluoro types – fine-tuning over the blue-to-amber (29 steps) and green-to-magenta (57 steps) colour ranges, or manual colour temperature setting over a range of 2500 to 9900 degrees Kelvin. Three custom WB settings can be created and auto white balance bracketing is available over a sequence of three frames.
Like the A7R III, the A7 III lacks an intervalometer, a multiple exposure facility and in-camera panorama stitching, but none of these is necessarily a deal-breaker given what else is on offer.
The processing options for JPEGs include 13 ‘Creative Style’ picture presets (with the option of creating up to six customised presets), eight ‘Picture Effect’ special effects, noise reduction is provided for both long exposures and high ISO settings, ‘Dynamic Range Optimiser’ (DRO) processing and a selection of multi-shot HDR modes. 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 also available for the dynamic range expansion processing. The HDR options also include an auto mode – when the camera captures a sequence of three frames with the correction applied automatically (again based on the brightness range in the scene) – and a selection of manually-set exposure adjustments from +/-1.0 EV to +/-6.0 EV, designated ‘Level 1’ to ‘Level 5’.
In-camera lens corrections are provided for vignetting, chromatic aberrations and distortion.
In The hand
Don’t get too excited about the touchscreen controls because, as with the A7R III and A9, the implementation is again limited to autofocusing functions, namely the selection (or moving) of a focusing point with a ‘Touchpad’ option which allows this to be done while using the EVF. Touch controls aren’t even available for browsing and certainly not for any on-screen setting duties which are all done the traditional way. However, there’s an excellent ‘Quick Navi’ control screen which provides speedy access to a large selection of capture functions, using the navigator controls, with adjustments made via one or other of the input wheels. The ‘Quick Navi’ screen not only provides various read-outs and status indicators, but also includes a real-time histogram, a dual-axis level indicator and an exposure compensation scale. An alternative ‘Function Menu’ control screen is available with the live view image and provides quick access to up to 12 functions. The A7 III has the improved menu design and layout that was introduced with the A9 and which uses colour-coded tabs for the chapters, page numbering (both displayed and total), more extensive use of labels for groups of related functions and a set of bar-type indicators to additionally indicate the displayed page’s sequence within the chapter. A customised ‘My Menu’ can be created to handily collect the mostfrequently used functions under the one chapter heading.
The control customisation options continue to expand and, while there’s a total of 13 controls with adjustable functions, there are four Custom buttons (marked C1 to C4) which are truly multifunction and assigned roles from lists which cover no fewer than 22 menu pages. Additionally, the ‘C’ buttons are separately assignable for stills, movies and playback. The four quadrants of the main navigator wheel (a.k.a. the “Control Wheel”) and its centre button also allow for customisation as does the ‘Function Menu’ control screen and, frankly, we can’t see anybody needing anything more. Two camera setups can be stored in-body and further four to a memory card for subsequent recall when needed.
Both the EVF and monitor displays can be configured with guide grids (selected from a choice of three), a dual-axis level display or a real-time histogram (so not at the same time), the frame for the phase-detect AF’s coverage (useful especially for tracking) and zebra patterns (with adjustable levels set between 70 and 100+) to indicate areas of overexposure. The 100+ setting is the minimum level setting and primarily only shows areas likely to cause some flare, and the threshold for blown-out highlights is steadily decreased with the lower settings. The viewfinder displays cover the exposure settings, battery level (including a percentage remaining read-out) and the basic file settings (size and aspect ratio). The monitor’s read-out display includes a much more comprehensive set of status indicators or, alternatively, just the image alone. Incidentally, the EVF is fully disabled once the monitor is tilted so there’s no danger of it being accidentally activated – and hence the monitor de-activated – should the proximity sensor in the eyepiece be inadvertently covered.
THE A7 III IS THE BEST VALUE ILC ON THE MARKET REGARDLESS OF SENSOR SIZE OR DESIGN CONFIGURATION. DO ALL THE COMPARISONS YOU WANT… NOTHING ELSE GETS CLOSE.
The image playback modes include nine or 25 thumbnail pages, zooming at up to 18.8x with JPEG/large files and a slide show function for auto playback with adjustable display times. The image review screens include a thumbnail with both highlight and shadow warnings, a full set of RGB and luminance histograms, and all the key capture info, including the ‘Creative Style’ preset and the DRO/HDR settings.
SPEED AND PERFORMANCE
With our reference memory card – Lexar’s 128 GB SDXC UHS-II/ U3 (Speed Class 3) Professional – loaded into the A7 III’s faster Slot 1, a burst of 107 JPEG/large/ extra-fine files was recorded in 10.553 seconds which represents a shooting speed of 10.13 fps. The average file size in this sequence was around 17.5 MB and the buffer emptied almost immediately after. Once again, we just picked an arbitrary point to stop the timing sequence and the camera would have happily gone on shooting at 10 fps for a lot longer (which is, it should be pointed out here, twice as fast the previous two generations of A7 models).
As we noted with the A9, it was transfixing to watch the 693-points PPD autofocusing continually, analysing the subject and adjusting the active points instantly to cover even very tiny shifts in the framing during continuous shooting.
Not surprisingly then, the autofocusing performance is truly superlative, enhanced by the near full-frame coverage and the very high number of measuring points which covers both tiny subjects and tiny changes in a subject’s position. Fast moving subjects – even those closing in at a rapid rate – are focused with consummate ease and consistent reliability. Eventually it was a case of seeing how we might be able to trip up the A7 III’s autofocusing… hyperactive dogs, erratic cockatoos and even water drops from a dripping tap; nothing got away. And, just sayin’, it’s less than half the price of the A9.
While 24 MP may not look as glamorous as 42 MP, as we’ve said on a number of occasions, it’s not so much about how many megapixels, as what you do with them and Sony is getting
very good at squeezing as much imaging goodness out of every one as possible. The extra-fine quality JPEGs are exceptional with plenty of crisply-resolved detailing, seamlessly smooth tonal gradations and a wide dynamic range (without resorting to expansion processing). Colour and contrast can, of course, be varied according to the selected ‘Creative Style’ preset and its adjustable parameters, but overall the colour reproduction achieves a pleasing balance between accuracy and saturation with, in particular, better handling of the reds and paler skin tones than we’ve seen previously.
The wide dynamic range translates into enhanced exposure latitude and more flexibility when shooting RAW in low light (i.e. there’s more scope to underexpose when using the lower ISO settings and then selectively brighten the mid-tones and/or shadows post-camera without creating excessive noise). With JPEG capture, the A7 III achieves a very good balance between definition and noise reduction processing thanks to the ‘Dual Gain’ circuitry delivering a much cleaner output to start with. There’s minimal loss of sharpness or colour saturation up to ISO 6400 and the image quality is still very good at ISO 12,800 and 25,600, but with some noticeable softening of finer details. That said, we decided to try out ISO 204,800 just for the fun of it and while chroma noise was in abundance everywhere, the shot would actually be usable if kept small. While a number of other cameras claim such stratospherically high ISO settings, the A7 III is the first we’ve seen where the image isn’t a join-the-dots proposition. In terms of its realistic high ISO performance though, the A7 III can claim another crown, easily bettering any other full-35mm ILC available (including its siblings).
We loved the A9 (and still do), but wondered whether the A7R III was the better choice given its potentially more flexible combination of high resolution and high speed… after all, not everybody needs 20 fps, but then, let’s be honest here, nor does everybody need 42.4 megapixels resolution either. So what about the A7 III which throws affordability into the mix? Shop around and you should be able to sneak in under the $3000 mark which means – and let’s cut straight to the chase here – it’s the best value ILC on the market irrespective of sensor size or design configuration. Do all the comparisons you want… nothing else gets close, including the A9 and A7R III. Forget any of the full-35mm D-SLRs… too big… or too slow… or both.
Smaller than the smallest full35mm D-SLR, the A7R III not only does 24.2 MP at 10 fps with full AF (and in 14-bit RAW, if so desired), it also delivers class-leading AF and high-ISO performance, the best battery life and both comfortable and efficient ergonomics.
It’s not perfect, of course, but eliminating anything that would increase the purchase price (such as a higher-res EVF, for example), the only real complaint is the lack of more touchscreen controls. Otherwise, you’d have to say Sony has got the balance absolutely right, with the result that the A7 III is going to be absolutely right for a great many photographers.
Monitor screen has tilt adjustments only and the res is 921,600 dots which is starting to look a bit stingy in today’s market. ‘Quick Navi’ control screen allows direct access to many capture-related functions and also includes displays such as a real-time histogram and a dual-axis level indicator. New joystick-type controller is primarily for AF point selection, but can also perform various navigational duties.
Hotshoe is Sony’s ‘Multi Interface’ mount so various other accessories can be powered from here too. Main mode dial includes two settings for custom camera setups and the ‘S&Q’ (Slow & Quick Motion) position for accessing a range of video framing rates from 100 fps down to 1.0 fps. There’s a total of four fully multi-functional Custom buttons, but various other controls can also be customised to some degree. Exposure compensation dial is marked to +/-3.0 EV, but up to +/-5.0 EV can be accessed via the shooting menu.
Live view screen components include guide grids, dual-axis level display and real-time histogram.
Autofocusing functions take up four pages of menus while the various assists (above right) have a full page to themselves.
The A7 III has Sony’s revised menu layout which is more logically organised and quicker to navigate.
Check out how the autofocusing system is working this subject… talk about precision.
Replay screen includes a full set of histograms.
A big upgrade is the provision of dual card slots with one being dual format for SD and Memory Stick Duo devices.
The A7 III’s expanded sensitivity runs from ISO 50 to 208,400 and while the image is quite noisy even at the maximum setting, it’s still actually usable provided you don’t need a very big image. All these images taken with the aperture set to f11 and the exposure time varied to compensate for the ISO adjustments.