As far as the camera and lighting, that is an art unto itself, and I'm only a -~~complete knob-~~ amateur photographer. But I'd start with changing the camera's exposure setting from automatic to a fixed value. It'll take experimentation to get right, but once it's set, you should be good for the rest of the shots in the scene. You've gotta be sure there's no incidental light from a window or anything, too.
EDIT: NM you said the camera had the same settings. Ugh...sorry. I have teh dumb tonight.