Recording up to UHD 4K is possible with frame rates up to 120p, using full 1:1 pixel readout without binning. Internal 10-bit 4:2:2 sampling is also possible in all recording modes and, if recording externally via the full-size HDMI A port, 16-bit raw output is also possible for even greater tonal reproduction and post-production flexibility. Additionally, two codecs have also been developed: XAVC HS, which uses HEVC/H.265 encoding to retain more detail at smaller bitrates, and XAVC S-I, which is an intraframe codec for consistent performance and quality at bitrates up to 600 Mb/s.
The high-speed, 120 fps recording also enables 4x and 5x slow-motion movie recording with the frame rate playback set to either 30p or 24p or, if moving down to Full HD resolution, an effective 240p frame rate is also available for even greater motion control. Additionally, suiting long-form recording, the a7S III does not have any recording time limits to allow for unlimited clip lengths. The camera’s physical design also features an improved heat-dissipating structure to promote longer possible recording times, up to an approximate 60-minute recording time at 4K60p.
Affording extensive customizable color and gamma controls, the a7S III allows users to adjust the gamma, black level, knee, color level, and more. Also, users can use the same S-Log2 Gamma Curve that is found on high end Sony Cinema cameras that squeezes up to 1300% more dynamic range into the video signal then traditional REC709, for increased post-production flexibility. HLG (Hybrid Log-Gamma) support is also available, along with the BT.2020 color space, for recording within a wide color gamut and, in addition to S-Log2, S-Log3 is also available for producing a 15+-stop dynamic range with increased grading control in the shadow to mid-tone regions of the image.