Scan Lines / LogiTech ScanMan Color 2000

It's probably not anything that you're doing wrong. I have a logitech
PageScan Color scanner (sheetfeed) and have to deal with the same
problem. A friend of mine also purchased the PageScan Color Pro and had
exactly the same problem. If your problem is the same problem we've
had, the lines are usually a dark green color and appear only in dark
portions of the picture. Our scanners came with calibration cards and
we both noticed that we could sometimes recalibrate several times and
virtually eliminate the lines (not always completely, but mostly
unnoticeable). I've also noticed that the lines are more noticable in
the Scanning software which came with the scanner. When I pull the
pictures into Fauve Matisse, they are less apparent. We both sent email
to Logitech. I never heard back from them. My friend got a response
and passed it along to me. It wasn't much help but they did mention
that recalibrating was a key factor in the image produced. I'm not
certain your problem is the same as ours. Mine also seems to have
gotten better with time (??). I have to zoom in most of the time now to
see the lines as they are very faint (and only in very dark areas of the
picture.)
In any case, I hope this helps somewhat. If you have questions, mail
me.

Jeff H.