i want to place an object A of color / material "invisible" in front of other objects and in the final render i'd like to see alpha=0 at the pixels that show object A.
So object A is in front of other objects that have normal color. A is marked as invisible but you can't see through but if you render a PNG you see a hole in the PNG where A was visible.
I hope it is clear what i want to achieve.
I saw some hints to check the "Sky" checkbox but that did not help.
Thanks for any hints,
Use Transparency, Mask Alpha 0.0 for the invisible material:
I'm sitting, waiting, wishing, building Blender in superstition...