A rotary format-mask carrier plate carries a plurality of removably supported format masks for originals to be copied and carries them back and forth between the copying station and a change station, where the masks can be exchanged for others and/or copied originals replaced by not yet copied originals. Downwardly extending projections on the format masks extend through and beyond corresponding openings in the rotary carrier plate. While a format mask is transported from the change station to the copying station, it rests on the carrier plate. When it reaches the copying station, the carrier plate descends an amount such that the projections on the format mask come to rest on correspondingly arranged stationary electromagnets, thereby transferring the weight of the format mask to the stationary electromagnets. The carrier plate drops a further amount, losing physical contact with the format mask at the copying station. In this way, shaking or vibration of the format-mask carrier plate, resulting from laying on and removal of originals and format masks at the change station, cannot be transmitted to the format mask and original presently located at the copying station.