In a nutshell, a description of a color negative mask is as follows: when the dyes are formed in a color negative, they have impurities (unwanted color absorptions) which taint their color. Collectively, these impurities form a negative orangish image (along with the regular dye image). Residual dye coupler, that which does not convert to dye during development, remains and forms a positive orangish image. It is orangish because the dye coupler was given that color during manufacture. The two images cancel one another. The dye impurity image thus has been "masked" by the dye coupler image. What results is a uniform orange color all over the negative, consisting of the mask (positive orangish image formed by residual dye coupler), and what it is masking, dye impurities (forming a negative orangish image). This uniform orange color is simply filtered out during printing and along with it goes the effects of the mask and the dye impurities, resulting in improved color in the print.
Last edited by RPC; 10-16-2013 at 12:31 PM. Click to view previous post history.