Konica Minolta bizhub C451 - Manual (Page 127)

Scanning 2
C451 2-88
Background Removal (Quality Adjustment)
The scanning density of the document background can be adjusted. When
documents printed on colored paper are scanned in color, the background
may become black. In that case, the density of the background can be ad-
justed.
1
Touch [Scan Settings] in the Fax/Scan mode screen.
2
Touch [Quality Adjustment].
3
Touch [Background Removal].