Abstract: The cassette comprises two pivotable guide members (6,7) which guide the photographic strip material (B) round a hollow cylindrical guide sleeve (5) which can be slipped onto a rotatably mounted, drivable winding core (4) and, on being slipped onto that winding core, locks into its operating position.

Abstract: Two pairs of pivotable flap clamps are arranged on a copy master stage in the area of its exposure window, each pair having flaps respectively disposed above and below the master plane. The pairs of flaps are driven by means of an electromagnet and can be symmetrically opened and closed relative to the master plane. In their closed state, the flaps hold the copy master on two opposing sides with their front edges. Additionally, spring elastic hold-down strips are provided to hold the copy master on its lateral sides. By means of the bilateral clamping of the copy masters with the two pairs of flap clamps, an absolutely flat position of the copy master is obtained. The positioning device is particularly suitable for processing copy masters in which short strips of film or individual images are spaced apart on a carrier strip.