Canon LBP710Cx User Manual page 584

3
Use / to adjust the density.
Density adjustment
Set a "+" value to increase the density. Set a "-" value to decrease the density.
Example adjustment of each density area
4
Press .
● If you want to also make adjustments on other density levels, repeat the operations in steps 2 to 4.
Maintenance
<High>
<Medium>
<Low>
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