a
reference to one of a
series of colors used in printing to
check that a proof (and the subsequent prints) is carrying the correct
weight of ink and that the printing
plate has been correctly exposed. When film is prepared for proofing, a
color bar is put on the
edge of each piece of film. This
color bar contains a number of colors including a patch of
gray that enables one to see whether all the colors being used in the print
job are balanced. If all is in
order the patch should appear as a neutral
gray; however, if the print carries too much ink the patch will be closer to black.