{{main, Image noise
Shadow noise or luminescence noise is an effect that
digital lightening
Digital usually refers to something using discrete digits, often binary digits.
Technology and computing Hardware
*Digital electronics, electronic circuits which operate using digital signals
**Digital camera, which captures and stores digital i ...
has on an image, specifically on the darker, or shadowed areas of the image. Brightening the image, especially in underexposed photos, brings out the "shadow noise" in such areas. Noise in digital photography is the analog to film photography's grain, or visible distortion that appears on an image. However, film grain tends to be less noticeable than noise, which can appear as distorted colors or artifacts on an image. A suitable analogy would be when a television begins to "snow" or experience "white noise", when static begins to appear on the screen, distorting or obscuring the image.
Correction
There are methods to correct shadow noise. Professional digital editing software like
Photoshop
Adobe Photoshop is a raster graphics editor developed and published by Adobe Inc. for Windows and macOS. It was originally created in 1988 by Thomas and John Knoll. Since then, the software has become the industry standard not only in raster ...
have the capability to eliminate some amount of noise, while other software, such a Band Aide or
Noise Ninja
Noise Ninja is a proprietary noise reduction application and Photoshop plugin which attempts to eliminate noise present in photos taken with a digital camera. It uses custom profiles for each camera to increase the effectiveness of the noise redu ...
are specifically designed around the process of eliminating shadow noise in a photo.