Hey Werner, vas geschieht? Yes, I was checking my work in the wiki, preparing some mix examples, and cant get the darn thing to work. Have not tried to supply a manually generated Z channel yet; still working on documenting the basics! Although I know that EXR format images honor the Z, as per my latest DOF rewrite. Don’t know if the Composite output node honors a supplied Z; I suspect not.
Mike_S: they connect,but don’t communicate. I really was trying to take the alpha channel from any picture (PNG) or RenderLayer node and use it as the Alpha channel to the Composite output node. yes 242a. ANY example will do, I can replicate. Nothing I try works. Even using a SetAlpha node etc.
For example, render a solid cube in the middle of the camera view. The cube is alpha 1, and the background is 0. In the Node Editor, add an Image input node and load up a JPG. Connect its Image output to the Image socket on the Composite Node. Connect the RenderLayer Alpha socket to the Alpha socket on the Composite Node. The Compositor should use the supplied Alpha to override the Image Alpha and thus render only the portion of the JPG that ‘overlays’ the cube. But no, it doesnt…so the question is, what does the Alpha input socket on the Composite Node do?
AND, I would think the Alpha input socket on the SetAlpha node would use an Alpha channel from a Renderlayer or PNG Image Alpha output socket, but no, it doesnt work either…for me. Probably cause I dont have some button clicked… Thx for anyone’s help!