If you're using our keyer, you'll find it under Quicktime, in the Video Filters menu. Your first choice, should be "VKey Filter". If, for some reason, that doesn't work for you, you might want to try the older, "GreenKey Filter". We're using VKey for this example, because it is the simplest and most powerful keyer, and it uses vector keying; a newer keying technology than the old-style chroma-keyers.