I'm making a "crater" (by deforming a plane), and I do not want the grey color of the plane to be present in the final render, i.e. I would like only deformation-caused shadows to be left, but make the plane transparent. I was expecting "shadow catcher" function to help, but it hides entire plane with all the casted shadows.
Essentially I'm trying to get rid of the plane color (to replace it with transparent) and keep shadows in the render. So far I have found no compositing or shader features to help me with that.



