Blending / compositing advice please

Hi FCP experts

I often see on film / tv nice blended or superimposed sequences of, well anything, but for example, simply shots of people, from different scenes. Is there a way to replicate this on FCP 7. When I'm mixing video tracks simply using opacity, the video image becomes thin and ghostly and often darkens. The more tracks used obviously the thinner and more transparent the images become.

Is there a way to blend video tracks in FCP while keeping the images relatively solid. So in fact only certain areas become transparent, and it's in these areas we see other video tracks. I suspect it's with composite modes, which I'm obviously no expert on. Is this the way these effects are achieved? In the industry would FCP actually be used for this - or is it more likely to be done with something like After Effects?

Many thanks for any help or ideas
Ben

Do some research on 'keying', and "mattes" That should point you in the right direction for what you are trying to do. Composite modes are more for blending layers to achieve a particular look.

And yes, while FCP can do this (and sometimes reasonably well), compositing should be done in a program like After Effects.