This page gives some basic details about the Coverage Render Channel and how it is used in compositing.
Overview
The Coverage Render Element holds anti-aliasing data based on the Render ID Render Element. When the Coverage Render Element is multiplied by the Render ID Render Element in compositing, it adds anti-aliasing to the Render ID channel, providing a quick object mask.
Parameters
The parameters for this render channel appear in the Parameters tab under the out Network and within the render elements node.
Name – A user-friendly title for the pass.
Deep Output – Enables deep output.
