12MP Full-Frame Exmor R BSI CMOS Sensor
UHD 4K 120p Video, 10-Bit 4:2:2 Internal
16-Bit Raw Output, HLG & S-Log3 Gammas
759-Point Fast Hybrid AF
The Sony a7S III is a video-focused full-frame mirrorless camera with a 12 Megapixel BSI CMOS sensor. It uses an all-new dual-chip Bionz XR processor, which offers considerably more horsepower, allowing for faster autofocus/auto-exposure as well as high bitrate video. The camera offers an ISO range of 80-102400, which expands to 40-409600. Sony claims that it captures 15 stops of dynamic range. The autofocus system has 759 on-sensor phase-detect points and supports eye and animal AF.
The camera has in-body image stabilization that can reduce shake by up to 5.5 stops. It has the highest resolution electronic viewfinder on the market (as of July 2020), with 9.44 million dots. There's also a 3.2" fully articulating LCD. The camera has two memory card slots, both of which can accept SD (UHS-II) or CFexpress Type A cards. It has both USB 3.1/3.2 Type 1 and micro USB ports, and can be powered using an external power bank.
Video is the big story, with the a7S III able to capture UHD 4K video at up to 120p without pixel binning. The a7S III can also record high speed (240 fps) Full HD video. Sony claims that the a7S III can record for up to an hour at 4K/60p thanks to improved heat dissipation. The camera offers both Long GOP and All-Intra compression, with a maximum bit rate of 600Mbps. It can record 10-bit 4:2:2 footage, and both S-Log2/3 and HLG are supported. Full-frame, 16-bit Raw footage at up to 60p can be output to an external recording. A full-size HDMI port , as well as mic and headphone jacks, are are available, and an XLR adapter can be purchased separately.