Lexmark C910 User Reference Manual page 243

Print Mode
Purpose:
To determine whether images are printed in a monochrome grayscale or in color.
Values:
Color*
Black & White
Toner Darkness
Purpose:
To lighten or darken text images, or conserve toner.
Values:
1–4 (4*)
Select a lower value for lighter grayscale images. Select a higher value for darker grayscale images.
Select a value of less than 4 to conserve toner.
1 is lightest; 4 is darkest.
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