Xante Accel-a-Graphix CT4, Руководство пользователя

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8-42 Color Management bb __________________________________
Scenario 1
You are working in the CMYK color space and your image appears
to have too much cyan. To correct this, increase the gamma on cyan.
When you increase the gamma for cyan, you decrease the amount of
cyan laid down during printing. Also, as you decrease the amount of
cyan laid down, its complimentary color, red, automatically increases
proportionately.
Scenario 2
Once again, your image has too much cyan; however, now you are
working in the RGB color space. You should increase the gamma on
red. This produces exactly the same effect as increasing the gamma
on cyan in the CMY color space (as described in Scenario 1).
If this scenario seems strange, keep in mind that RGB are additive
colors and CMY are subtractive colors. For example, since red is an
additive color, increasing its gamma will make the overall image
more red. (Think of it as adding more red.) On the other hand, since
cyan is a subtractive color, increasing its gamma makes the image
less cyan (and consequently, more red). In this case, you are
subtracting cyan, leaving more of the other two primary colors,
magenta and yellow which together make red.
Setup Color Separations
Color separations are critical to professional printing. Because
media vary so drastically in ink absorption, Photoshop provides a
special Separation Setup feature under Preferences in the File menu.
When you select the Separation Setup, its window appears (fig. 8.38)
with a multiple of options to fine tune your output. Photoshop
converts an image from the monitor’s RGB additive color space to a
printer’s CMYK subtractive color space using monitor, ink, and
separation setting information.