I have been using an HP ScanJet 4100C with my linux computer for a number of years. I primarily use it to scan old pictures into GIMP for restoration or enhancement. Even though I always kept the outside of the glass clean, I have noticed in the last year that the inside of the glass was developing a cloudy residue. I finally decided to do something about it. Before getting started, I locked the scan head using the sliding green button on the bottom of the scanner. If you open the cover, there...
