A common bugaboo of digital photography, noise is the appearance of color artifacts in a digital image. Mostly noticeable in the shadow areas of images captured at higher ISO ratings, the image processors used in many current digital cameras utilize noise-suppression software to minimize the appearance of noise artifacts. Heat build-up due to continuous shooting in hot environments can also cause noise artifacts within digital images. Noise is considered the digital version of grain in film negatives.bhphotovideo
In some cameras, noise reduction can be activated or switches on automatically at slow shutter speeds. Note that noise reduction often requires more time for the photo to be written to the memory card, during which you will be unable to take a picture.
This is the grainy look you find in a digital image caused by image artifacts. It may also appear as flecks of color that should not be there. It is usually noticeable in shadow areas, and generally produced when shooting in low light. It is caused by high ISO required for low light shooting. Noise is almost always unwanted and unattractive.
Random errors and fluctuations in an image. Noise can be distracting across a sequence of frames.
– A mottled or grainy appearance in images caused by electrical fluctuations on the image sensor. Noise becomes more pronounced as the camera s ISO (light sensitivity) is raised, causing decreased detail and distorted colors. Noise is not always visible in small versions of photos used for online posting but can become obvious in large prints or cropped photos.
Misinterpreted pixels found in your digital image, usually occurring in longer exposures. Can be seen as misplaced or random bright pixels in the picture