you will see those in most images where you do spheres as a cloud, fire, or any other such thing. I have to admit, that this is ONE place that I touch up in images I do by just blurring the area with the blur tool in Photopaint or photoshop. I hate doing that...I like bryce to finish the image... anyhow, you can try the suggestions above, but I've 'been there done that' and it always seems to come back to post render touch up. later BT