Although you might not have a lot of control over the artwork you need to scan, you can still prepare ahead of time to improve your chances of success. So the first thing you want to do before scanning is to prep your original. Here are a few tips:

• Start with the best available original. Don’t use a copy print if you can avoid it. Use a print that was made recently from the original negative. Older prints are sure to have some scratches, or their colors might have aged over the years. If the print is housed in an album or frame, carefully remove it before scanning unless removal will damage the picture.
• Start with the largest print that fits on your scanner. If you can choose between a 4 x 6 print and a 5 x 7 print, use the larger print. Because of the grain of the color emulsion in the print, a larger version is likely to be sharper and, more importantly, to have a larger tonal range -- the range of colors from lightest to darkest.
• Clean the print and your scanner glass before you scan. If you scan a dusty print, or if dust covers the glass platen or scanning bed, you end up with an image that has dust spots that you must remove in your image editor. Dust the print carefully with a cloth and use Windex and compressed air on your scanner’s bed.
• Make sure the image is aligned properly on the scanner glass. If you scan a print that’s rotated slightly, you can always straighten it out in your image editor. Of course, you lose some quality, particularly when straightening horizontal and vertical lines that could have been scanned with proper alignment in the first place.