Format assembler for photographic printer

A format assembler for a photographic printer having a control system controlling component movements that include movements of interchangeable lens modules with different lens arrays, a paper advance along a printing plane, and a film negative advancer and orienter, said format assembler comprising:

• a. a carriage movable along a path parallel with said printing plane and extending in the direction of said paper advance between said lens modules and said printing plane;
• b. a mask carried in a fixed position on said carriage to be interchangeable with other masks having different shapes;
• c. said mask having a predetermined shape related to light transmitted through preselected lenses of said lens arrays;
• d. means for positioning said carriage in a predetermined plurality of positions along said path for locating said mask in different positions wherein said mask blocks said light transmitted through different preselected lenses of said lens arrays;
• e. said predetermined shape of said mask being arranged to block off light through preselected lenses of one lens array when said mask is in a first position to allow exposure of one longitudinal side of a paper area and then to block off light transmitted through preselected lenses of a second lens array when said mask is in a second position to allow a successive exposure on the opposite longitudinal side of said paper area without advancing said paper;
• and
• f. said control system including means for controlling said positioning of said carriage in programmed relation to said component movements.