Paper film

As its name implied the film was made of paper (which was a stable material, unlike cellulose nitrate film), on which images were offset printed. The film had a width of 28mm which, thanks to being perforated in the middle, resulted in roughly the same picture area as with 35mm film. It was projected, not with transmitted (diascopic), but with reflected (episcopic) light. Thus film width, perforation, and illumination system all meant that only film made for this contraption could be projected. Even if REFCY projectors were “not that expensive toys” (Sugimoto[1990], 256), this would seem to have been a disadvantage.