Hi, all. I use my 5DMkII for macro video in an underwater housing. With video, we want to lock in a shutter speed, and vary the aperture and ISO (gain) for proper exposure. I'd like to "assign" ISO to the shutter speed wheel, so I can easily change the ISO in real time and judge my exposure immediately on the exposure meter, rather than having to hit the ISO button, guess at a proper ISO, accept it, then judge. Is there a way to do this, either in standard or Magic Lantern-ish firmware?

Sorry Shane, but this cannot be done via the regular Custom Function menu. I can't speak as to Magic Lantern, sorry. Hopefully somebody else will have some input on that.

Is there an auto ISO option? maybe with settable max and minimum settings? Just a thought