Measurement and Control of Color Opacity

Ink companies supply to the printing industry a variety of colors with various opacity levels, yet seldom do we see opacity specifications for both standard and non-standard inks. With so many variables (paper stock, light source, dot overlap, etc.) complicating color printing, control of all color properties, including opaqueness, becomes vital. Errors in color opacity are often mistaken as trapping and density problems. Our industry must put controls on color opacity, especially between press and proof, in order to add consistency to an interactive process. The importance of color opaqueness and its control is described and method of measurement introduced. Specific examples are discussed which show significant color error due to differences in color opacity when overlapping halftone and solid color areas, with primary emphasis on applications to color proofing. The importance of color opaqueness and its control is described and method of measurement introduced. Specific examples are discussed which show significant color error due to differences in color opacity when overlapping halftone and solid color areas, with primary emphasis on applications to color proofing.