Terri, Tell your partner with the roid complex, he can very easily change film in the roid without a dark bag. There is a very minor and completely reversable alteration that allows for the removal of a dark slide. With that alteration he can make cardboard negative carriers for the roid. That will allow him to shoot as many shots as he would like. His actual image will still be 3x4 but he can use the uncut 4x5 sheets.