Epson Stylus Pro 4000 Reference Manual page 215

Sliders
The color enhancement slide bars adjust the indicated options in
a range of -25% to +25%.
Drag the slide bar to the right or left with your mouse to adjust
the settings. You can also type a value from -25% to +25% in the
boxes next to the slide bars.
ColorSync
This setting automatically adjusts printout colors to match colors
on your screen. Select this setting when printing scanned
photographs or computer graphics.
Note:
Be aware that the ambient light and the age, quality, and settings of the
monitor can affect the quality of your color matching.
Printing with Mac OS X
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