Oki B412dn User Manual page 291

BG SETTING
DRUM CLEANING
HIGH HUM. MODE
QUIET MODE
Change the setting if there is unevenness in the image quality.
0 Corrects the variation in print results that is caused by temperature and humidity
conditions, as well as differences in print density and the frequency of printing.
Change the value if the background is dark.
OFF Sets whether to perform drum cleaning before printing. This may improve image
quality.
OFF Changes fusion temperature as a measure to prevent paper from curling.
OFF Applies the low-speed printing mode for reducing print noise.
290