The inversion distance problem

A light tight tunnel extends over the top of a diagnostic x-ray table. A film cassette is mounted for reciprocating in the tunnel between an x-ray exposure position and a position in which the cassette is unloaded or loaded with film automatically. Unexposed films are dispensed one at a time into the cassette from a feed magazine at one end of the tunnel. After exposure, the film is ejected from the cassette into a receiving magazine at the same end of the tunnel.