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The Epic Interactive Encyclopedia 1998
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Epic Interactive Encyclopedia, The - 1998 Edition (1998)(Epic Marketing).iso
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Halftone_process
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1992-09-02
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Technique used in printing to reproduce the
full range of tones in a photograph or other
illustration. The intensity of the printed
colour is varied from full strength to the
lightest shades, even if one colour of ink is
used. The picture to be reproduced is
photographed through a screen ruled with a
rectangular mesh of fine lines, which breaks
up the tones of the original into areas of
dots that vary in frequency according to the
intensity of the tone. In the darker areas
the dots run together; in the lighter areas
they have more space between them. Colour
pictures are broken down into a pattern of
dots in the same way, the original being
photographed through a number of colour
filters. The process is known as colour
separation. Plates made from the separations
are then printed in sequence, yellow, magenta
(blue-red), cyan (blue-green) and black,
which combine to give the full colour range
(see four-colour process).