Canon® EOS Digital Photography Photo Workshop

5.4. MOIRÉ PATTERNS

Have you ever seen a distracting pattern on a person's jacket or shirt when watching television? This effect, known as a moiré pattern, is caused by geometric elements of a subject and image sensor conflicting with one another. It's one reason that portrait photographers generally advise clients not to wear geometric patterns in clothing when being photographed.

In dSLRs, moiré occurs because pixels are arranged in a specific matrix pattern that can, on occasion, conflict with patterns on a subject. The patterns aren't visible through the viewfinder, because you're not looking at what the image sensor is picking up. If you have a subject with a tight geometric pattern on an article of clothing, then you should shoot a test shot. When you download the test shot to a computer, make sure to view it at 100 percent and at the final size you'll be using for the image because these are where a moiré is most likely to present itself — different magnifications of the digital image in image-editing software may represent it differently.

NOTE

Occasionally, a moiré pattern may be visible on the monitor but not in print form.