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The aperture shape is controlled by the aperture camera projection options, such as those found in PxrCamera. You can switch projections while retaining these controls.

Sides: The number of diaphragm blades does not technically control bokeh, but does control the shape of your blur circle (but not how light is distributed within it). Changing the number of sides causes our once perfect circular highlights to facet with as many sides as specified (three sides, for example, produces a triangle).

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