Visible crew/equipment: In the scene when Bedford hits the ceiling in the Cavorite-covered chair, the thick metal cable attaching the chair to the ceiling is visible to the right of Bedford. It is NOT, as I initially suspected, part of a lamp or some other bit of scenery - at one point you can actually see it move as it pulls Bedford up and down.
Visible crew/equipment: Paul Mantee's helmet reflects two stage lights often when he is supposedly outside.