This article explains the settings and values for the Corona AO shader.
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The Corona Ambient Occlusion (Corona AO) is a shader that can be used to color the concave and convex areas of a surface. By default, when used as diffuse color, it will darken crevices and cavities of objects while also brightening flat and raised areas. The Corona AO shader can also be used to create advanced materials, such as rusted metal, worn wood, and scratched paint, or to provide artistic control over the overall scene appearance.
