[{{ paag_blur.png|a) the circle boundary (emphasized in yellow) is significantly less distinct due to blur}}] **Blur** refers to the parts of a depiction which become less distinct and less defined.

Unintended blur can happen as the result of applying the averaging of values excessively in an attempt to lessen [[aa|aliasing]] artifacts.

Blur itself can be perceived as an unwanted artifact if it destroys the clarity of a part which was originally intended to appear crisp.

Blur may be used intentionally, for example to emphasize perceptual effects like soft shadows, a lack of detail in some light/shadow situations, [[motion blur]] or unfocused areas.

Shown in the example are an aliased circle, an anti-aliased circle and a blurred circle.

further reading:
  * [[wp>Defocus_aberration|Defocus aberration]]
  * [[wp>Bokeh|]]