Fujitsu ScanSnap S510M Operator's Manual page 215

If the following symptoms are observed, lay the material over a piece of white
HINT
paper to scan.
•
The output image is not in a suitable size (when [Automatic detection] is
selected).
•
The outline of the material is shaded.
•
Black lines appear around the material cut out in an indefinite shape.
6.2 Using the Carrier Sheet
ScanSnap S510M Operator's Guide
white paper
193
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