Epson Expression 800 Reference Manual page 65

The image cannot be printed, the printout is garbled, or the printout is not an image.
Problem
Your printer may be
causing the problem.
Your printer software
may be causing the
problem.
Color stripes appear when scanning film.
Problem
Your scan is being
distorted by an effect
known as Newton's
Ring.
A line appears in the scanned image when you're using the ADF unit.
Problem
The narrow window
near the ADF's
mounting bracket is
dirty.
Troubleshooting
Solution
Check that the printer is properly connected to the computer and is
correctly set up. (See your printer manual for instructions.)
Check that your printer software is properly installed and configured.
(See your software manual for details.)
Solution
Try scanning the film upside down. Newton's Ring is an optical
phenomenon that occurs when two very thin membranes such as
film surfaces or soap bubble surfaces meet.
Solution
Clean the window with a soft, dry, lint-free cloth.
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