This The Normals channel outputs the orientation of every surface in the image through representing the orientation of the its Normal vector at this point.
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Maxwell can output two different Normals channelchannels, depending on the coordinates system you need to consider:
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This information is useful in compositing , when you need to perform adjustments dependent on the World orientation of a surface (to mimic dirt, dust, illumination, shadows, etc).
The render (left) and the Normals channel in World coordinates (right)
Normals channel in Camera coordinates
This mode analyzes each polygon normal vector and represents transforms it in to Camera-space coordinates, where the polygons aligned from left to right appear in red, the polygons aligned from down to up appear in green, and the polygons aligned with the camera depth axis appear in blue.
This information is useful in compositing , when you need to perform adjustments dependent on the Camera orientation of a surface (lens effects, etc).
The render (left) and the Normals channel in Camera coordinates (right)