Yes it is completely Glas! I was wondering about the black parts too, but I catched me a Glas (in real world) and made a scene like the CgI and I saw the black areas too!!! probably there are to strong black areas, but they can occur and are a part of Glas refractions... I think so and learned it that way... I will try with your advices!!! Thanks a lot!! :attn: