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This page provides information on the Object ID Render Element which isolates individual objects with different colors based on IDs for compositing purposes.


In Maya, Object IDs can be added as an Extra V-Ray Attribute. Two or more objects in the scene can share the same Object ID.

The Object ID Render Element creates selection masks based on Object ID that shows each object (by Object ID) in a solid unshaded color.

UI Path: ||Display Render Settings button|| > Render Elements tab > Object ID




To use render elements, select from the Available render elements column and click the Add button to add the passes you wish to generate at render time. When you render the scene, the added render elements listed in the column on the right, will also render, which can be viewed from the VFB window's channel drop-down menu.

For more information on the parameters on this dialog, see the Render Elements tab page.




The parameters for this render element appear in the Attribute Editor under Extra V-Ray Attributes.

Enabled – When enabled, the render element appears in the V-Ray frame buffer.

Deep output – Specifies whether to include this render element in deep images.

Filename suffix – The text added to the end of the rendered file, when saved as a separate file (e.g. myrender.objectID.vrimg).


Common Uses

The Object ID Render Element is useful for isolating geometry in a scene based on the Object ID. This means that items can be isolated by use of a matte created from the solid colors within the Object ID pass. 



Object ID Render Element


Matte created in composite by using only the red channel




Original beauty render


Glow and brightening added to the composite using matte created from
Object ID Render Element red channel (as a mask in composite)





  • Select the geometry that an Object ID Render Element is needed for.


  • Add the Object ID attribute Attributes > VRay > Object ID while the shape node is active for the geometry.


  • Set the Object ID to the required value. Note: each number corresponds to a different color.


  • Open Render Settings and go to the Render Elements tab and from the Available render elements add an Object ID render element.






The name of the Object ID render element must consist of the name of the Object ID itself, a dot and then any other string to be properly read in Nuke. For example, VRayObjectID.example . Do not include numbers in the name.