Epson Expression 800 Reference Manual page 63

The edges of the document are missing from the scanned output.
Problem
The document is
positioned incorrectly.
Color is patchy or distorted at the edges of the image.
Problem
The document may be
letting in external light.
The image is faint or out of focus.
Problem
The document is not
positioned correctly.
Your software settings
may be incorrect.
Troubleshooting
Solution
The document table has non-readable areas around the edges.
Reposition your document so that the image you want to scan is within
the readable area.
Solution
If the document is very thick or warped at the edges, the edges of the
image may be discolored. Cover the edges of the document with
opaque paper to block outside light.
If the document extends beyond the edge of the document table, part of
the document may not be in contact with the table. Change the position
of the document.
Solution
Check that the document is placed flush against the document table.
Adjust the brightness option in your software to a darker setting. (In
EPSON TWAIN Pro, adjust the Gamma setting.)
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