While most photographers see digital noise as a bad thing, there are times when intentionally including some can work. To achieve these effects, you’ll need to use noise reduction software on a portion of your image. Here are examples of “good” noise:
• Exposing for the rich colors sunset will likely give you some noise but leaving it in the entire scene except for the disc of the sun itself will create visual impact.
• The long exposure necessary to capture star trails will give you a noisy image. You might need to keep the noise in the sky to achieve crisp star trails, but try eliminating it from the foreground elements.
ADAPTED FROM PRACTICAL ARTISTRY: LIGHT & EXPOSURE FOR DIGITAL PHOTOGRAPHERS BY HAROLD DAVIS (O’REILLY, 2008; $30)