We just got this new all in one printer, scanner, fax machine it is an HP Officejet 6978. It replaces our previous machine which was a HP LaserJet Pro MFP M127-128 (it stopped communicating through the outside world either through a usb connection or the wifi network and would only show up as a hard drive which we couldn't access). Anyway I use our machine to scan in my artwork. I have never had much luck with the HP software which always gives weird grainy scans but when I used windows fax & scan with our old device I could get really clear high resolution images like the sample on the left.
Compare this with the sample on the right which uses the same technique in terms of the artwork but is unfocused and pixelated. I cleaned the glass on the scanner but the dust spots remain. Both samples are shown at 100% resolution. I tried both the HP software and the Windows Fax & Scan with the same results. I am scanning in color, set to scan a photo, and at 1200 dpi just as I did with my previous machine. I have spent several hours using various software and techniques to make sure the artwork is flat against the glass and this is the best I could do. Please help. . . Any advice is welcome.