Shadow Catcher


OctaneRender® improves realism by implementing the Shadow CatcherThe Shadow Catcher can be used to create shadows cast by objects onto the surrounding background imagery. The shadows cast are not limited to simply a ground plane but can be cast onto other surfaces of varying shapes. to create shadows cast by objects onto its surroundings (Figure 1). The shadows cast are not limited to simply a ground plane, but can be cast onto walls and other objects in the scene that represent objects in the 2D environment map.


Figure 1 : Shadows appear in the transparent parts of the image where the shadow catcher objects were placed


To use the Shadow Catcher:

  1. Make sure there is a light source in the scene. This can be a direct light source, or an Emission map connected to a scene object.
  2. Place a DiffuseAmount of diffusion, or the reflection of light photons at different angles from an uneven or granular surface. Used for dull, non-reflecting materials or mesh emitters. or Universal material on the shadow catching objects in the scene and enable the Shadow Catcher option at the bottom of the material parameters.
  3. Alternatively, there is a dedicated Shadow Catcher material that can be used instead of the Diffuse or Universal materials.
  4. In the Kernel Settings, activate Alpha ChannelA greyscale image used to determine which areas of a texture map are opaque and which areas are transparent. and make sure Keep Environment is disabled.