Tips on Scanning Resolution

Today many of us have a scanner whether it is for personal or business use. Many people make the mistake of assuming the higher the scan resolution the sharper the scan; however, this is not always true. It will also eat up a great deal of hard disk space. The tips below will help in your scan resolution decision.

Scanning Line Art: Easiest type of image to scan because of limited color levels. You should make sure the image is as clean as possible. If the image is on colored paper you can adjust the threshold - higher threshold, lighter image. Scan line art at the same (SPOT) resolution as the output printer; i.e., output printer 600 dpi, scan image at 600dpi.

Scanning Continuous-tone/Gray Scale/Color Images (photographs, etc.): Of course the best photos to scan have a good balance of grays/colors. If, however, the photo is not perfect you adjust the Brightness and Contrast controls of your image manipulating software. Remember Brightness will wash out detail, and Contrast will sharpen the dark and light differences. Scan at twice the HALFTONE resolution of the output printer. Huh? Without going into the details of desktop publishing, if your output printer is 300-360dpi, scan at 50-100dpi; 600-720dpi printer, scan at 100-200dpi; 1200dpi printer, scan at 200-266dpi; 2400dpi printer, scan at 225-300dpi.

If scanning to fax a document, scan at 200dpi lineart.

If scanning text to print or OCR, scan at 300dpi lineart.

If scanning for a web site or monitor image, scan at 72dpi.

A great site for scanning tips is http://www.scantips.com.