A self-developing type photographic apparatus includes a self-developing packet having a pair of juxtaposed sheet elements and a supply of film-processing fluid provided between the sheet elements with at least one of the sheet elements forming part of an area which is to be coated and developed by the fluid. The packet is adapted to be advanced through a pressure-generating gap defined between a pair of juxtaposed rollers. One of the rollers has a rigid sheet-contacting surface, whereas the other of the rollers has an outer resilient material layer. Various embodiments for facilitating the uniform spreading of the film-processing fluid over the film area are disclosed, particularly in the border regions thereof.