Many of my multiple exposures are done intentionally on the individual frame, planned out, and occur on a roll in-between single exposures. Sometimes I will do what I call "Multi-exposures," using 9-20 exposures of the exact same subject on the same frame. But for my favorite multiples, I shoot an entire roll, then reload it into the same or a different camera and shoot over it with another subject. These are called "Blind Doubles" as I have no idea what will fall on each frame. When I load the same roll the second time backwards and expose through the wrong side, these doubles have redscale images exposed with color images.