To provide an apparatus which, when a long wait time occurs while a photosensitive material is temporarily fixed on an exposure drum, decreases waste of the photosensitive material to the utmost while eliminating the stand-by state.

The apparatus is equipped with: two or more cartridges each housing a photosensitive material, a transport mechanism to cut the photosensitive material housed in one of the cartridges and to transport the material to an exposure mechanism; a mechanism to hold the photosensitive material for exposure with image data; and a back transport mechanism to transport the photosensitive material to the empty cartridge after a specified period of stand-by state after the photosensitive material is exposed. After the photosensitive material is transported back, the photosensitive material in the cartridge is again transported to the exposure mechanism.