Thanx a lot for your suggestions. To Erlik: I use to set very low ambience settings, so it's not a problem. But I checked, in case I left the ambience driven by the texture, no way: ambience was dark grey at 3,3. To Incarnadine: thanx a lot, I think the problem is the overlapping of shadows of the various radials, the negatives were set to "Don't cast shadows" just to avoid this problem. The sky was atmosphere off and disable sunlight, plus black background. To Aldaron: same as above, the shadow setting in the sky lab was of no influence... or maybe it's this I get wrong? If I have Disable Sun Light and Atmosphere Off, the shadow setting in the skylab continues to affect my scene? Really thanx again very much to all three. I'll let you know how it progresses :) Stefano