Lexmark X4850 - AIO INKJETPR P/C/S 27/30PPM WLS B/G/N User Manual page 43

The Scan dialog has three main sections: the Settings tab, the Adjustments tab, and the Preview area.
From here
Settings tab
Go to
Scan Settings
Reduce Background Noise
To
Select a preset scan setting according to the color and
document type of your scan.
Note: Select Custom Settings to customize the scan setting
manually instead of using a preset scan setting.
Remove smudges and light background shading in color
documents.
Scanning
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