a leader section l of the filmstrip f projects from a plush lined light trapping slit 11 in a throat 13 of the cartridge c and has a forward end portion whose width is approximately one half of the width of the remainder of the filmstrip the 35 mm camera includes a number of known elements such as a loading chamber 15 for receiving the cartridge c a flash ready lamp 17 for a built in electronic flash now shown a low light warning lamp 19 a viewfinder window 21 a pair of substantially parallel film rails 23 and 25 a film exposure window 27 an objective lens 29 a film take up chamber 31 housing a film take up spool 33 or drum a manually operable latch 35 for securing the back door 3 closed a pressure plate 37 spring supported on the inside of the back door for holding successive frames on the filmstrip f flat on the pair of film rails 23 and 25 during film exposure at the exposure window 27 and a shutter release button 39 manually depressible to initiate film exposure to load the 35 mm camera 1 the film cartridge c is inserted in the loading chamber 15 then an intermediate portion of the film leader l is placed over a metering sprocket 41 to position one or more of the perforations p in the leader in engagement with respective teeth 43 on the sprocket in addition the forward end portion of the leader l is placed over the take up spool 33 to position one or more of the perforations p 39 in the leader in engagement with respective teeth 45 on the spool an initial film.