I recently worked on a spot directed by a still photographer who does photographs with up to 400 layers. I asked him if his studio was permanently painted green, and he said no--he got better results from gray.
Not sure if he's using a combination of colour and luminance or just luminance. Might be worth a look, though, especially with dark skin and a white outfit.
I've shot full body green screen with dark skin and I didn't have a problem. I think it would be harder if it was partial body green screen with green kinos, as that super-saturated light has a tendency to spill everywhere. A green cove lit by space lights isn't nearly as saturated.
I used large soft sources as edge lights the last time; I think it was a maxi on each side bounced into an 8x8 to create shine in the skin.
The white clothing bit is just dumb. Dark skin looks nice when it's either overexposed a little or has a big source reflected in it. A white outfit might interfere with that somewhat. My suggestion is that you find out who's idea that is to shoot dark skin in a white outfit and then dip the outfit in whatever that person is drinking.
Art Adams | Director of Photography
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