This page provides information on the Object Select Node in V-Ray for Blender.
The Object Select Render Channel stores only the object(s) called out with a specific Object or Material ID.
This effect is reversible to create a render element that excludes a particular object or objects according to Object or Material ID.
When rendering this element out, it will also include a filter and alpha passes separately to help make it easier to use when compositing.
||Node Editor|| > Add > Render Channels > Object Select
Name – The name of the render channel.
Use Mtl Id – When enabled, V-Ray is going to extract the contribution of all objects that have a material with the specific material ID assigned to them.
Object IDs/Material IDs – List of selected IDs included in this render pass.
Affect Matte Objects – Controls whether or not matte objects will be present in the render element.
Consider for AA – Allows you to enable or disable the the sampling of the current render channel for antialiasing.
Invert Selection – Use the opposite of the selected objects in the render pass.
The Object Select render element allows items to be isolated for easier control at a composite level. In the example shown below the robot arms at the front of the frame have been color corrected and tinted blue.