Depth of Field
Depth of field effects (dof) happen in all real optical devices to a certain extent. It is heavily used in photography and film as a style element. In computer graphics dof is usually generated using ray tracing techniques which increase rendering times considerably. The depth of field plugin generates those fast as a post process. It needs a depth buffer for its calculations.

Out of Focus
'Out of Focus' is a fast version that works without depth information. It creates a blur with constant radius over the complete image and is a good complement to 'Depth of Field'. It offers some extra functionality as well. It's possible to use a custom drawn lens in addition to the generateable ones. 'Out of Focus' also offers background distortion for semi transparent areas.

Lens Aperture
A cameras lens aperture greatly defines the look of its blur (Bokeh). Therefore the filters offer the possibility to alter the lens apertures form to simulate several kinds of real cameras. This is important if you want to comp cg elements into real footage or just want your cg shot to fit in with the rest. A wide range of apertures can be simulated. The Out of Focus plugin provides the possibility to completely replace the aperture with a custom image. The aperture's form is most apparent in highlight spots.

Highlights
In reality very bright image parts are predominant when being out off focus (see image below). Unfortunately common graphic formats cut of bright parts. Thus the plugins offer the possibility to select parts that are supposed to be brighter and give those boost.

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