I see many photos of models on black background where the foreground floor of the shot is so reflective it looks just like water. Is this some kind of plastic or mylar that is laid down on the floor, or is it linoleum? I'm sure they don't flood the studio floor with an inch of water, but it sure looks like it. Sometimes the effect is smooth and sometimes it is rippled like water. How is this done? I want to do it! Thanks.