Moiré is often described as a noticeable pattern, such as herringbone, crosshatch, checkerboard, spots or a dotted pattern, in a scanned image. One common way to reduce moiré is to convert the scanned image into a vector image (rather than a bitmap) if your scanning software supports that feature. However, the most common way to correct moiré is to take advantage of the scanning software's "de-screening" feature. Some scanners have a built-in de-screening feature that will reduce moiré automatically. In either case, de-screening will increase scan time, and will generally increase the memory requirements for image processing. Also remember that de-screening should only be used when scanning halftone or printed material--not when scanning photos or plain text.

Formerly part of Computer Currents, Stephen J. Bigelow's Computer Advisor column has been resurrected on computeruser.com as a daily tech tip column. Find Stephen at www.dlspubs.com.