I was wondering if anyone is willing to help me by explaining how a common effect that's used in many movies is actually done. I've seen movies have the effect where there is a single subject in the middle of a shot. The subject is not really moving but everything else around the subject is in fast motion. If you don't really know what I'm talking about I'll give an example. Say that there is a guy in the middle of a camera shot. And the guy is only looking straight at the camera but isn't moving(that much). But a large group of people are moving in fast motion around him. If anyone knows what I'm talking about please try to help me.