Feature Request - Auto ISO exposure?

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ActionJackson

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Feature Request - Auto ISO exposure?

PostThu Feb 02, 2023 7:30 pm

Hi,

I recently got a bmpcc 6k g2 a few days ago. I love it, and will still keep it even without this feature.

I noticed the auto exposure through shutter speed or aperture. But those can easily take away bokeh, require pulling focus again, or give motion blur / take it all away and look unnatural.

But do you guys have any plans for, or will you ever add the ability to get auto exposure through ISO? Something that would work for both dual native ISO's (under 1000, and 1250+).

My hope was that I could record in BRAW, film from outside and sunny, to inside and darker with the same aperture / shutter speed, cut the clip, and change the ISO of the clip as needed.
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John Paines

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Re: Feature Request - Auto ISO exposure?

PostThu Feb 02, 2023 7:53 pm

This feature will never be implemented for braw, because ISO is not a tool of exposure. It's just metadata, which applies a display curve to the footage (one alterable in post) but isn't altering the exposure of the sensor, which is determined solely by the f-stop and shutter speed. Whether the ISO is 100 or 1000, the exposure is the same if the f-stop and shutter speed is the same.

If you're talking about movies, you're not going to want to fool with shutter speed for every shot, so the only way to achieve a particular fx is the f-stop.

Even if you're shooting Prores, you really don't want to rely on the ISO as a tool of exposure, beyond choosing one of the two circuits based on overall lighting levels.
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Jeffrey D Mathias

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Re: Feature Request - Auto ISO exposure?

PostFri Feb 03, 2023 3:15 pm

If you are not utilizing the full dynamic range of the camera, like if doing something for SDR rec.709, you can set your exposure so as not to clip the outside (bright). Then in Resolve you can adjust the exposure with a grade when moving between darker and lighter (inside and out.)

For example: if your final print has 8 stops and your camera 12 stops, you should be alright with a 4 stop difference from the dark to light areas.
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