V-Ray: using render elements for fast selection of objects in post production

VrayWireColor is used to select and alter elements of final remnder in post-production. very often these selections are not 100% accurate and they produce edges around the selection. for perfect accuracy most companies use MultiMatte element instead. Multimatte element uses 3 colors manily - RGB.

To select specific color, you select channels tab in Photoshop and with CTRL pressed you can select mask with perfect accuracy. MultiMatte can be generated from Object ID or material ID. You can use manu MultiMatte elements so you are not limited to three selections in post-production. Watch the video below that explains it in detail.