Canon LBP7210Cdn Manual page 337

NOTE
About the color adjustment
There are three methods to adjust color as follows:
Clicking the color buttons surrounding the adjustment grid deepens
the color by one increment.
Clicking a desired color on the adjustment grid moves [Preview
Image] to the clicked point.
Drag [Preview Image] onto the desired color.
The X (horizontal) and Y (vertical) values for [Adjusted Position] show the
position of [Preview Image].
A sample image after adjustment is displayed in [Preview].
Confirm the settings, then click [OK].
The [Quality] sheet reappears.
Click [OK].
The [Print] dialog box reappears.
Click [OK] or [Print].
The printer starts printing.