So here is a camera being used as a projector, ie a light source is inside the camera body projecting through the gate where a piece of film is held. The left one has a 135mm (Apochromat, Kinoptik) lens BUT the right one has a cinema 35mm lens with focal length of 40mm. The image sizes are below. The camera is at its furthest travel to the end of the optical bench so the point of this exercise is to establish the potential image area that can be photographed with different lenses OR how much another moving image frame can be REDUCED. And with a 40mm lens the answer is a LOT. With the 135mm lens (the frame for this seen marked on the screen) you could fit 7 super 16mm images horizontally across. The bottom left image shows a projection that is about 97mm in width.
