Does the Sony a7S III Have Dual Gain ISO?

The recently released and long-awaited Sony a7S III marks a significant step forward in terms of camera technology, bringing some remarkable dynamic range and 10-bit 4:2:2 internal recording. As the camera falls into the hands of more reviewers, a question remains: does it have dual gain ISO?

Josh Yeo had a few days to play with the camera last month and just had chance to put his thoughts together in this video. Like Gerald of Gerald Undone, Yeo was so impressed that he’s decided to invest in a pair of a7S IIIs, as the camera is an excellent fit for his line of work. Be sure to check out the video in full to see what gets Yeo so excited about this new camera and which features he didn’t even realize that he needed.

Not many users have had a chance to play with the camera for more than four days, and there’s still something of a mystery as to what happens when you flick over from ISO 12,800 to 16,000. As seen in Gerald's extensive testing (check out 18:43 in this video), there’s a significant drop in noise that is yet to be explained. If there is dual gain ISO, why isn’t Sony shouting about it as part of its marketing for the camera? Yeo suggests that there might be a different explanation, but you’d still expect something to appear in the camera’s documentation.

What are your theories? Be sure to let us know your ideas in the comments below.

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Brian Knight's picture

Now I wondering if/where the switchover is on my cameras!

Nicolas Thulliez's picture

I wonder if the dual ISO is working for stills ?

Allan Pakett's picture

I read in another review that for stills the switchover is at ISO 2000. That is about what is expected for a Sony sensor with that pixel density.

Brent Rivers's picture

This s3 release will hopefully lead to some firmware updates on the other bodies. The joy is in having the best of breed for each type of shooting. Can't wait to start shooting/editing with it.