The film in question is 35 mm unsprocketed intended for traffic surveillance. I've modded my Kodak Instamatic 500 to accept unsprocketed film in the 126 cassettes. This was done by cutting off the feeler peg that usually finds each sprocketed exposure on the original films. It's my second time exposing non-native film in a Insta 500 and the results are similar - overlapping frames. But the results were not so bad. Well, it depends on your intentions. I wanted to see if I could use the unsprocketed film in the 126 cassettes. And that I could. I just have to advance the film twice for each exposure, to not end up with overlapping exposures. And in the process expose the first of those in the palm of my hand or something. The lens is just wonderful! Its so sharp! Actually I have modded one to fit my M39 mount cameras. One bonus feature which occured when I cut off the sprocket feeler peg was that the camera is 'ready' to expose after each wind.