What is the Sony A7 III?
Announced on 27th February 2018, the Sony A7 III is a full-frame mirrorless camera and the replacement to the Sony A7 II. It’s designed to be a general-purpose camera and is aimed at experienced enthusiast photographers. Sony already has high-end all-rounder, the A9, but at over £4,000/$4,000 it’s out of reach for most enthusiast photographers.
The Sony A7 III price tag is half the cost of the A9 and it sits between the high-resolution Sony A7R III and the video-centric A7S II as the more affordable option. Like its predecessor, the A7 III has a 24Mp, sensor but according to Sony it’s a new chip.
Sony has stuck with 24Mp for the A7 III and on the basis of one of our recent Twitter polls, I think that will be a popular decision giving a nice balance between file size and detail capture (and noise control). It also maintains the separation between the A7 Mark III and the A7R Mark III.
Although the sensor is backside-illuminated (BSI), it’s not the same sensor as is in the A9, but there is a front-end LSI which Sony says doubles the readout speed from the sensor. According to Sony, this results in the focusing in low light being almost twice the speed of the A7 II in low light and the focus tracking is twice as fast.
The sensor and processing engine enable an overall sensitivity range of ISO 50-204,800, indicating that the A7 III should perform well in low light. In fact, Sony is claiming a 1.5EV improvement in image quality overall.
Sony’s 5-axis optical in-body image stabilisation is on hand and is claimed to give a 5EV extension in the hand-holdable shutter speed.
The Sony A9’s autofocus (AF) system is phenomenal and while the A7 III doesn’t have exactly the same system (that would require the same sensor), it has the same 693-point phase detection points and 425 contrast AF points.
These points cover 93% of the imaging area, making it easier than with the A7 II to track moving subjects. In addition, the system is sensitive down to -3EV, which means it should be effective in low light.
There’s also Sony’s Eye AF mode that helps you target the most important part of a portrait subject.
Sony has given the A7 III a maximum continuous shooting rate of 10fps. As with the A7R III when it shoots at 10fps, there is a brief blackout at this rate with the A7 III, if you want a continuous live view feed the rate can be dropped to 8fps.
With a fast card installed, the A7 III can shoot at 10fps for 177 Standard jpeg images, 89 compressed raw images or 40 uncompressed raw images. Furthermore, it’s possible to shoot at 10fps using the mechanical or the electronic shutter, so the camera can be made silent if necessary.
The A7 III is capable of recording 4K (3840 x 2160) footage to a memory card at 30p/25p and 60Mbps or 100Mbsp. There’s also S-Log2 and S-Log3 available for recording flat footage ready for grading, and a Hybrid Log-Gamma (HLG) picture profile is provided for displaying video direct from the camera on HDR (HLG) compatible televisions.
When the camera is set to record 4K video it uses full pixel readout without pixel binning so it gathers around 2.4x as much data as is needed for 4K movies. It then oversamples the files to produce 4K footage with better depth and dynamic range.
There’s also a Zebra display, Gamma Display assist and proxy recording.
In addition, Full HD footage can be recorded at up to 120/100p (NTSC/PAL) for slow-motion playback.
One of the issues for the Mark I and Mark II A7-series cameras is low battery life. Sony addressed this for the A9 and A7R III with the NP-FZ100 battery. This battery has also been used in the A7 III and it has a claimed life of 710 shots when the screen is used to compose images.
|Sony Alpha 7 III|
|Date announced||27th February 2018|
|Price at launch||£2000/$1,998 (body only), £2,500/$2,198 with 28-70mm lens|
|Sensor||Full-frame (35.9 x 24mm)|
|Effective pixel count||24.2Mp|
|Sensitivity range||ISO 50-204,800|
|Reflex AF system||N/A|
|Live View AF system||693-point wide area phase detection AF|
|Max shooting rate||10fps with full AF and metering|
|Max video resolution||4K (3840 x 2160)|
|Storage||Dual card slots, Slot 1: SD(UHS-I/II compliant), Slot 2: Memory Stick Duo/SD(UHS-I)|
|Viewfinder||0.5-inch OLED with 2,359,296 dots|
|Screen||Tilting 3-inch Touchscreen with 921,600 dots|
|Dimensions||126.9 x 95.6 x 73.7mm|
|Weight||650g with battery and card|
Build and Handling
As far as I can tell, the A7 III has the same body shape as the A7R III. It’s small for a full-frame camera, but has a decent grip on the front and a small but pronounced thumb ridge on the back. Together, these grips and their textured coating help the camera stick in your hand while you’re shooting.
It’s good to know that the camera is dust and moisture resistant.
I like the physical control arrangement of the A7 II with two exceptions, the location of the video activation button and the method of autofocus point selection. Happily, Sony has addressed both of these issues with the A7 III.
The video record button, which is on a corner of the body on the A7 II has been moved to the right of the viewfinder on the A7 III. That means it’s within easy reach of your right thumb and it’s far easier to operate it without making the camera wobble.
Sony introduced a mini-joystick style controller for setting the AF point with the A9 and it continued on to the A7R Mark 3. It has also made it on to the A7 Mark 3.
In another change from the Mark II, the A7 Mark III has an AF-On button on its back, just to the side of the thumb rest.
In case you haven’t guessed, I’m a fan of touchscreens because they make things like setting the AF point, making menu selections and setting adjustments more intuitive.
Sony has given the A7 III a touchscreen, but as on the A7R III and A9, it hasn’t gone the whole hog. You can’t tap on the options in the main or function menus to make settings changes for instance. However, you can use it for setting the AF point, even when you’re looking in the viewfinder if you like, and you can use it to zoom quickly into images to check sharpness.
I’m still keeping my fingers crossed for a firmware upgrade to increase the level of touch-control.
Viewfinder and Screen
The A7 III has a 0.5-inch OLED electronic viewfinder that gives a good clear view of the scene. That’s about as big as you want a screen so close to your eye because when I’m looking at it I find I have to move my eye to check the edges.
It would be nice if Sony could make the active AF point a bit more visible, perhaps by making it red. The black marker can be quite hard to see at times.
It’s good to see that the A7 III has a ‘My Menu’ option to which you can assign up to 30 menu items for quicker access. It’s a very useful addition given the length and complexity of the camera’s menu.
It’s also possible to customise the function of 11 of the buttons of the A7 III, and there’s a total of 81 functions available.
I’ve been able to shoot with the Sony A7 III for a few hours and so far impressed with it.
Its low light autofocusing isn’t quite as good as the Nikon D850, which has superb low light focusing, but it’s good. I was able to photograph a pair of dancers in a dimly lit room filled with smoke and the low contrast didn’t cause much in the way of problems.
Of course, one issue is selecting the right focusing mode of the shooting situation. In some situations, for example with a relatively uncluttered or motionless background, Wide Focus area is a great choice because the camera latches onto a subject that moves randomly with more success than when you try to follow it with a small spot in the viewfinder.
Similarly, Expand Flexible Spot allows you to target an area and then the camera follows it, but it can sometimes jump to a different part of the scene.
Eye AF, which by default is assigned to the Center button can be extremely useful, especially as it works in continuous focusing mode. I found it very helpful when shooting portraits or photographing the dancers, but it doesn’t always spot the eyes so you have to be ready to react.
With 24Mp the A7 III isn’t going to match the 42Mp A7R III for detail, but for much of its native sensitivity (ISO) range it captures a high level of detail.
Even images captured at ISO 51,200 look good. The jpegs have a slight exture visible at 100% and show some signs of noise reduction, but they’re not objectionable. I’m looking forward to seeing what the raw files can do when the software is available to process them.
The A7 III has a maximum sensitivity setting of ISO 204,800. Which although we’ve seen it before, is a crazily high setting that allows photographs to be taken in very gloomy conditions. However, that setting is an expansion setting for a good reason. At that value, although I’ve seen worse, the images can suffer from false colour and noise. They could still be usable for news reporting or evidence gathering – or those situations when you just need an image.
Exposure and Colour
The A7 III’s viewfinder and screen can display the image as it will be captured so you can adjust the exposure before taking the shot. I found myself adjusting the exposure compensation dial quite a bit during my time with it at the press event. I’ll look into this in more detail when I have longer with the camera.
I’ve mainly used the camera in its auto white balance setting and I noticed the colours in shots of the same scene varying a bit depending upon the image composition. It’s not a dramatic shift in colour, but when the images are side by side it’s noticeable. Again, this is something I want to look at it more detail at a later date.
Although I’ve shot with a production sample of the A7 III, I want to shoot a wider range of subjects before passing final judgement. However, it feels like a good all-rounder with an extensive features set. It’s handling is much improved by the addition of the joystick control and touchscreen (although that could be better still) so it feels more refined than its predecessor. The autofocusing is also fast and more decisive so it seems like it could be used for shooting sport at a reasonably serious level.
Meanwhile, the silent shooting capability and good noise control will give it appeal to social and wedding photographers.
Sony is pitching the A7 III against the likes of the Canon 6D Mark II, which is a popular choice amongst enthusiast photographers and I think Canon should be worried.
Should I buy the Sony A7 III?
It’s a little too early to say for certain, but if you’re thinking of buying a full frame camera, I’d give it some serious thought and not rush into buying a Canon 6D Mark II just yet.
The A7 III’s fast and silent shooting credentials, clever autofocusing and 4K video capability, along with the high image quality make it worthy of consideration, especially given Sony’s growing range of high-quality optics.
Follow the link to browse and download full-resolution sample images
Sony Alpha A7 III Sample Images