Fujitsu ScanSnap S510M Operator's Manual page 70

3. Adjust the side guides to the document width.
Move the side guides so that there is no gap between the document edge and side guide on
both sides. Doing so can eliminate skewing of the document during scanning.
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Document
When you use the stacker, scanned document sheets are stacked on the
stacker in the collated order when they have passed through the ScanSnap.
Use the stacker as described below.
1. Pull out the stacker toward you.
Stacker
2. Extend the stacker.
Side guide