Epson Stylus Color 640 User Manual page 37

Advanced Printing
5 If you want to specify individual color correction values, use
the sliders to increase (drag right) or decrease (drag left) the
settings listed below.
Brightness
Makes your image lighter or darker.
Contrast
Increases or decreases the difference between the bright or
dark parts of an image.
Saturation
Makes colors more vivid or less vivid.
Cyan, Magenta, Yellow
Increases or decreases the amount of the three ink colors
that combine to make a full-color picture. Use these sliders
to fine-tune the color balance in your printout.
6 Click OK to return to the printer settings dialog box.
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