Abstract: An apparatus and method for processing bulk quantities of photo-sensitive film received in individual film cassettes is disclosed. The apparatus, which can be adapted for use with either roll-type film or disc cartridges, comprises a light-tight enclosure surrounding a film preparation device, a cassette opener for opening the film cassettes and a source of illumination designed to provide light for the apparatus operator during inspection of the cassettes. A control circuit actuated by the cassette opener is interconnected to both the source of illumination and a movable shutter in the light-tight enclosure. Upon actuation of the cassette opener, the control circuit extinguishes the source of illumination and moves the shutter to an open position to provide access to the film preparation device, all in a manner which ensures that the source of illumination has been extinguished before the cassette opening operation is completed and the shutter means reaches its open position.