Are there numbers printed on the back of 120/220 rolls of film? I recently tried to load an old TLR and there is no start mark with which to line up the arrows with but there is a ruby window. I have been told that there are [or used to be] numbers on the paper side of these films that can presumably be seen through a ruby window on such a camera. I tried it again with a roll of 220 film, but there were no numbers and I'm once again guessing as to where the start of the roll is. Does anyone know? Thanks.