I have two layers. One is cropped, the other is not. I have the cropped layer on top of the uncropped one. The cropped image is the static frame held version of the person not talking. The layer on bottom is the original video clip. Both layers are at 100 opacity. The static image should remain the same as the original layer continues to play. However, it gets darker. Removing the bottom layer removes any darkness from the top layer. But the top layer is a static image at 100 percent opacity. Why is it effected by the layer below it? Both layers are at normal opacity. Again, a static image is on top so it shouldnt be changing shadows or color.
If you look at the Effect Controls panel for the upper clip, is the Opacity Blend Mode set to Normal?