SONY

Sony has filled the last gap in its full-frame lineup with the A7 III. With a newly developed full-frame 24.2-megapixel back-illuminated Exmor R CMOS image sensor, the same advanced autofocus engine found on the lauded A9 and A7R III, and 10 frames per second (even in fully silent shooting mode), there is quite a lot to unpack with Sony's latest professional mirrorless camera. Some might be tempted to label it "prosumer," but it may just challenge how robust a camera can be and still be given that moniker.
Sony A7 III Key Features
Newly developed full-frame 24.2MP back-illuminated Exmor R CMOS sensor with Evolved Image Processing
Wide ISO range of 100 - 51,200 (expandable to ISO 50 - 204,800 for still images)
15 stops of claimed dynamic range
Autofocus system features 693 phase-detection AF points covering 93% of image area, 425 contrast AF points and Sony's fast and reliable "Eye AF"
Continuous Shooting at up to 10 fps with either mechanical shutter or Silent Shooting and full AF/AE tracking
5-axis optical in-body image stabilization with a 5.0-stop shutter speed advantage
4K UHD video with full pixel readout and no pixel binning across full-width of full-frame sensor
The longest rated battery life of any mirrorless camera at 710 shots per charge

Dual SD card slots
SuperSpeed USB (USB 3.1 Gen 1) USB Type-C terminal
Camera Body and Design
If you've held a Sony Alpha camera, you probably have noticed that they tend to follow a very similar design path. Even when they are different, like the subtle body changes to the A9, the general aesthetic is the same. Holding the A7 III feels exactly like holding the A7R III...because they are exactly the same. From a body design perspective, it is impossible to visually tell the A7R III and the A7 III apart aside from the model number on the front and back of the camera.
If you're new to the body and want to compare it to the A7 II, the biggest and most noticeable difference is on the back of the camera, where Sony removed the AF/MF and AEL switch and changed it to a joystick/toggle. This same change was made on the A7R III and allows you to more easily navigate a menu or adjust focus points while shooting. Though the A7 III has a touchscreen and the control wheel on the back of the camera are useful for most of the things you might find yourself needing the joystick for, it's still an addition that many customers asked for and therefore Sony delivered.
Other changes include moving a few of the custom function buttons around and relocating the video record button, which used to be up near the shutter button, to the rear of the camera to the right of the EVF.
Speaking of the EVF, the A7 III features a high-resolution, high-contrast, fast-start XGA OLED Tru-Finder with approximately 2.3 million dots for extremely accurate, true-to-life detail reproduction. Standard or High display quality settings are available for both the viewfinder and monitor as well. The Mark III's EVF is also noticeably larger than the Mark II's, with a magnification of 0.78x versus 0.71x.
The new camera also features what Sony is calling 'My Menu' functionality, which allows up to 30 menu items to be registered for instant recall when needed. You can also apply star ratings to your still images through the camera controls for easier image playback and review, and edit the first three characters of all still image files. Additionally, there is a total of 81 functions that are assignable to 11 custom buttons, and the camera is both dust and moisture resistant.
The A7 III and its 24.2 megapixel sensor
Opting for a smaller and more manageable 24.2-megapixel sensor, the A7 III is equipped with a back-illuminated Exmor R CMOS image sensor that is paired with a front-end LSI that Sony says effectively doubles the readout speed of the image sensor, as well as an updated BIONZ X processing-engine that boosts processing speed by approximately 1.8 times compared to the A7 II.
These components work together to allow the camera to shoot at faster speeds while also enabling its impressive ISO range of 100 - 51,200 (expandable to ISO 50 - 204,800 for still images) and an overall 1.5 stop improvement in image quality over the A7 II. The camera also features the same ~15 stops of dynamic range at low sensitivity settings found on the A7R III, that Sony says ensures outstanding overall performance at all settings and in all shooting conditions, with significant advancements in accurate color reproductions of skin tones and the vibrant natural colors.
The A7 III can also output 14 bit RAW format even in silent and continuous shooting modes, and is equipped with a 5-axis optical image stabilization system that results in a 5.0-stop shutter speed advantage.
Pros
New 24MP sensor offers excellent image quality; Outstanding high ISO performance and dynamic range; Improved JPEG colors; Improved build quality; Fast autofocus; Excellent 4K video; Very good battery life.
Cons
Buffer clearing can be slow even with fast UHS-II cards; UHS-II support only on one card slot; No losslessly compressed RAW option; Dedicated battery charger not included; Menus are still confusing; No built-in flash.

Price and availability
The Sony A7 III began shipping in 2018 for about $2,000 USD for the body and $2,200 in a kit with the FE 28-70mm f/3.5-5.6 OSS lens. In Canada, list price is $2,600 CAD for the body and $2,800 for the kit.


Source: D. C. and mundophone