You'd be better shooting it against a blue or greenscreen as Alan suggests. Shooting against a white backgroud will give you exposure problems as it is too bright and will force the camcorder to close down the iris and let less light in. This will result in underexposure of anyone or anything in front of the background. If you have manual exposure on your camcorder then use it and see how it looks, but whatever you do don't set the camcorder to auto.

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