Authoritytgm007718
https://www.loc.gov/pictures/collection/tgm/item/tgm007718
tgm007718Scope NotePhotographs produced from negatives, by transfer photo processes, or, in the case of photograms, by the direct action of light on light-sensitive paper. Tonal values are usually the same as those of the subject shown. Do not confuse with continuous tone photomechanical prints, such as COLLOTYPES and WOODBURYTYPES.