Canon MG6400 series Online Manual page 89

Select Light, Normal, or Dark for Brightness, and click OK. The current settings are
displayed in the settings preview on the left side of the printer driver.
4. Complete the setup
Click OK on the Main tab.
When you execute print, the data is printed at the specified brightness.
Related Topics
Setting the Print Quality Level (Custom)
Specifying Color Correction
Adjusting Color Balance
Adjusting Intensity
Adjusting Contrast
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