1. A xerographic system for developing X-ray sensitive plates of differing sizes enclosed in optically opaque covers comprising: an input station into which an exposed plate and its cover is inserted comprising means for removing said plate from said cover, a development station for producing an image from said exposed plate onto some recording media, means for storing a plurality of plates of differing sizes, means for charging said plates, an output station into which an empty cover is inserted comprising means for determining the size of said cover, and means for inserting a charged plate into said cover, means for transporting plates through said input station, said development station, means for storing, means for charging and said output station, in that order, and wherein said means for storing is responsive to said output station determining means to supply to the charging means and thereafter to said output station a plate of a size corresponding to that of said cover.