Mon Oct 07, 2013 6:36 pm
Pretty much my own understanding of autoiris in film mode is that it is trying to pump as much exposure onto the sensor as it can w/o clipping the image. Exposure is information so it's trying to get you the most information for post.
It is the same as exposing 500T as 320 or even 250 back in the days of film. It should also produce lower noise as you are getting darks a bit above the noise floor, and when you crush back down, you'll crush most of the sensor noise. Though truthfully in film mode, I just meter.
Adrian Sierkowski
Director of Photography
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