Bleach fix is a process that is needed in
order to complete color print film processing with a few steps.
After processing in the color developer,
a bleach is introduced to remove all silver in the emulsion since the
silver, having done its job of attracting and instructing color dye
clouds, is no longer needed.
After bleaching removes the rest of the
silver, all that remains are individual color dye clouds in the several
layers that now contain the image itself. A thorough, controlled
washing then removes remaining unused halides and color couplers.
The image on film is then chemically
fixed for permanence. A number of washes and a chemical stabilizer are
applied to complete processing.
The film is then dried in a dust-free
environment. What emerges from the chemical metamorphosis is an
emulsion consisting of three (four with some films) semitransparent dye
layers, each exhibiting varying densities of color. All the dye layers
combine to produce a visible full-color image.
After the film is completely dry, it can
be printed. The color negative is then inserted into a film carrier.
Enlarger light is passed through a set of calibrated gel or dichroic
filters of yellow-, magenta-, and cyan-colored material. This light
goes through the negative and is then projected onto a piece of color
The paper's construction is very similar
to that of the film itself. There are some differences—principally, the
paper's top, middle, and bottom color-record layers (which are
light-sensitive) respond to the colors red, green, and blue,
respectively, compared to the film's top-to-bottom sensitivity of cyan,
magenta, and yellow. As with color print film, the paper's three
color-record layers, once light-sensitized and chemically processed,
combine to make a full color image that mirrors the color nuances and
tonal range of the original scene.