Are you saying you shot footage of a person pretending to fall in a hole on green screen? If yes, you can use position keyframes to move them so they fall down the hole. Have you created your ground layer with the hole yet? Just duplicate it, move it to the top layer above the green screen and add a mask around the front of the hole and ground so it will be in front of the green screen footage when the actor falls down the hole…think of the ground layers as a sandwich bread between the actor.
Stephen Smith
Utah Video Productions
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