A photographic printer is loaded with two webs of photographic paper, and produces photographic prints by exposure thereto. Initially, the photographic paper is advanced from two photographic paper rolls in parallel. Those two are combined together to constitute a photographic paper roll unit. The photographic paper is cut to obtain photographic paper sheets, on which an image frame is formed. In one embodiment, the photographic paper roll unit includes a single axial core which extends through axial holes of the two photographic paper rolls positioned at an interval L1, and is fitted thereon. The photographic paper rolls include a spliced region for splicing two consecutive photographic paper strips to one another. The spliced region is detected from a single one of the two photographic paper rolls in combination.