I was recently given a Grafmatic film back for 5x4. It seems to take 6 sheets on some kind of spring loaded system, kind of like the magazine on my old Lee- Enfield. Only problem is that there seems to be only one septum inside, should there be six? I have never seen one of these before, let alone used one. Does anyone have experience with this magazine and do they hold the film sufficiently flat? Love to hear your thoughts.