Hi everyone. I've been pondering the idea of trying some type 55 with my mamiya 645. It may be a stupid question but when using the polaroid backs, is there some way to get more than one exposure per 4x5 sheet or is it a one shot per sheet deal. I'm just curious because at about $65 per 20 sheets it seems a little wasteful to only use a fraction of the emulsion area. I didn't know if maybe the mamiya polaroid backs had some mechanism to allow more full use of the sheet. Thanks for any info.