Separation Negative Characteristics for Photomechanical Reproduction.

The basic characteristics desirable in separation negatives for color-reproduction work are graphically illustrated by following a simplified photomechanical reproduction process. A technique of flashing the separation negatives has been worked out with which these characteristics can be obtained in practice. This controlled flash technique actually simplifies the making of separation negatives, since image exposure and development time can be standardized for any given masking procedure. The determination of flash exposure is outlined, and can easily be made from simple density measurements on the copy being reproduced. Other beneficial effects derived in color- reproduction work from using flashed separation negatives are described.