I have some footage that was shot on a white cyc, but the background looks gray. When I try to CC it to get the BG anything near white, the subjects get blown out. Have tried masking and rotobrushing the subjects, but I am getting a wavey effect on playback because the mask isn't perfect no matter how hard I try.
Is there a plug in for this? Is there another way to isolate the white/grey in the back? Any help is greatly appreciated!!
Without seeing your footage nobody can advise specifically.
Pushing the gray to white without effecting skin tones is tough. The best option is some kind of procedural matte combined with some careful manipulation of curves or levels. Show is a screenshot and we can give you a better idea.
This is why you need an experienced DP on set that knows how light and to read a scope or at least a histogram. Lighting against a white cyclorama requires quite a bit of skill and two separate pools of light. It's nearly impossible with just a couple of instruments unless they are really big soft sources that you can feather off the subject and on to the walls.