Oce Color System 200 Operator's Manual page 29

Black Adjustment
The black area of an original can be more clearly copied by adjusting the gray scale. Use this key to prevent black areas from
being copied as solid black or to prevent an original with many black characters from being copied too lightly.
Black Adjustment adjusts only black without influencing other colors.
Enhance black Weaken black
Standard mode
k
Gloss Adjustment/Sharpness/Black Adjustment
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