ANSI PH3.31

Description / Abstract: The methods outlined in this standard are intended primarily for testing enlargers for amateur and professional use. More-critical tests may be required for at least some functions of enlargers for photogrammetry, photoengraving, and other special purposes. Some characteristics of enlargers, for example, convenience of operation, nicety of finish, and sturdiness, are not readily subject to specific testing. Nevertheless, it is recognized that they are important and