Vincent Bockaert,

Posterization or Banding

Smooth tonal gradations in the sky. This exaggerated example shows "posterization" or "banding" due to a lack of tones. The histogram is combed with wide gaps between adjacent tones.

When performing image manipulations such as tonal conversions in low bit environments (e.g. 8bits/channel mode) only a limited number of tones may be available to describe a certain area of the image, as shown in this exaggerated example. This causes visible "banding" or "posterization".

This article is written by Vincent Bockaert,
author of The 123 of digital imaging Interactive Learning Suite
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