YupI used exactly that technique to do this film. Couple of colour ranges and a difference matte, mainly for the edges. And some roto-matting for the hoover pipe. And lots of garbage mattes thrown in for good measure
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Sheep!,
Sun 21 Nov 2004, 23:35,
archived)
I also saw somethingabout blurring the backgound of what's behind the moving footage, which simultaneously gives lightwrap AND sorts out the problem with the blur. I suppose you'd make it by making an inverse matte of a copied layer of your background footage, heavily blur it and put it over the top of your foreground plate...
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Sun 21 Nov 2004, 23:45,
archived)