The word "photomechanical" refers to a process that combines photography and mechanics. It describes techniques or methods that use photography to produce mechanical effects or replicate images.
JAY DeFEO Untitled c. 1975 - 76 Collage of photomechanical reproduction and gelatin silver print 9 1/2 by 3 15/16 in. (miandn.com)
The «Unidentified» photographs will be shown alongside eight photomechanical prints of legendary portraits and images from the 1970 Multiples, Inc. publication, Artists and Photographs by Lawrence Alloway, which come from CCS Bard's own holdings of Warhol's work. (bard.edu)