I have to shoot stills while a film crew it taping a commercial. Sound is not an issue as they won't be recording sound - just that I have to use their lighting and find an out of their way position to shoot. My main concern is the inside shooting at night, when there will be a warm, low light "look" created, and I'm concerned that my shutter speed will have to be too low to stop the action of the models. I'm sure there are photographers that do this all the time, as in movie sets, but I've never done it and am nervous knowing that I won't be able to add a light here or there if needed. Does anyone have advice for me?