Oki C 9400 - Manual (Page 335)

The subtractive primaries are Cyan, Magenta, and Yellow (CMY). Printing processes use
subtractive primaries.
With subtractive primaries, we start with a white background (usually paper ) and add
translucent inks of cyan, magenta and yellow to subtract certain wavelengths of light.
For example, cyan ink on a page appears as cyan because the ink removes components of red
light and reflects green and blue, which we perceive as cyan.
In theory, a combination of the three subtractive primaries should produce black. In practice,
pigments used in toner are not perfect and the combination usually gives rise to a dark
green/brown instead of black. For this reason, in many color output devices, a separate black
toner is used to produce grays and black (in shadows and black text for example). This is the
CMYK (Cyan / Magenta / Yellow / Black) model and is the method most widely used in the color
printing and printer industry.
The OKI ® C9000 Series Printers use separate cyan, magenta, yellow and black toner cartridges
to generate high definition color images.
Color Adjustments
Certain images such as bitmaps sometimes print with a strong hint of a particular color. Images
that look fine when viewed on a monitor may not necessarily print that way.
The color that appears to dominate the picture will vary depending on factors such as
The scanner or other input device having a bias towards a particular color.
The monitor's inability to represent certain colors on-screen.
Color Adjustment Using the Software Application
Many software packages provide a way to reduce the amount of any of the process colors put
on the page in relation to the others.
Example
You find that all of your graphics have a tendency to contain too much blue. To compensate
for this, reduce the amount of cyan or magenta, which combine to produce blue (if you do
this, bear in mind that other colors containing cyan or magenta will also be affected). An
alternative would be to increase the amount of yellow. This has the advantage of increasing
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