I am shooting a Ghost story for holloween, any way how do i shoot a scene where all actors are clear but the ghost in the scene is see threw? I am using final cut..
there are a lot of ways. The most traditional way is to lock off the camera on a tripod, compose your shot, and shoot the scene with "humans" first, then with the "ghost" Make sure they don't overlap each other! Then in post, lay the ghost footage on top of the regular footage, clip out everything you don't need, and cut the opacity down about 50%.
This is called double exposure.
You can also get a giant piece of glass low-gloss and use reflections to do it all in one shot. It's tricky but looks really good if you understand optics.