Caustics is an effect that is produced when light rays are reflected or refracted by the materials within a scene, which can produce light patterns on the same object or on other objects. The Caustics Render Element stores the effects that are generated with Caustics photon mapping, enabled from the Caustics in the Render Settings window. This render element is useful for enhancing or toning down caustic effects in the composite.

The Caustics Render Element is useful for changing the appearance of caustic elements after rendering in a compositing or image editing application. Below is an example of its use.

Original Beauty composite

Caustics Render Element

Brightened caustics

Compositing Formula

The V-Ray Caustics Render Element is added to the Beauty render to form the final image.