This page offers information about the Caustics Render Element in V-Ray for Cinema 4D.
Overview
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 objects in the scene. The Caustics Render Element displays these effects, generated with Caustics photon mapping. It is enabled from the Caustics rollout under the GI tab in the Render Settings window. This render element is useful for enhancing or toning down caustic effects in the composite.
This render element can be used to enhance the rendered caustics after the render is complete. See the example.
UI Path: ||V-Ray|| > Render Elements > Caustics
How to add a render element to a scene

Properties
Enable Deep Output – Specifies whether to include this render element in deep images.
Color Mapping – Applies the color mapping options specified in the Color Mapping rollout of the V-Ray tab in the Render Settings window to this render element. This option is enabled by default.
Consider for Anti-Aliasing – When enabled, anti-aliasing is used where possible.
Filtering – Applies an image filter to this channel.
Vfb Color Corrections – Applies the post-render color adjustments made from the VFB.
Denoise – Enables the render element's denoising, provided the Denoiser render element is present.
Example: Enhance Caustics
In this example, the caustic reflections on the yacht are enhanced after rendering using the Caustics Render Element. The yacht is selected using a Cryptomatte mask, and the Caustics effect is first subtracted from that object and then added back enhanced. This achieves greater fine-tuning of the caustic effect.
