Why does document scanning produce a grey haze over the printed copy

"Hi,

Clean the scanner glass and the inner side of the document cover with a soft, lint-free cloth (microfiber is recommended), moistened with a little glass cleaner. If you see lines in your scans or copies, clean the left side of the glass carefully.

Caution: Do not spray glass cleaner directly on the glass and do not press the glass surface with

any force.

Here is a link which shows what to do (not your model but idea is same for all) http://printscan.about.com/od/howto/ss/c...

Here is a link to the user manual for your model, scroll to page 219-220 to view area to clean. https://files.support.epson.com/pdf/wf25..."

you have the density set to a positive number , anything but pure white is then interpreted as pale blue or grey