Hi richcz3, Yeah, just last night I tried playing with the gausian blur along with the blend options DMM just mentioned. Both produce nice results for situations like this. I was just as pleased with the results as you are (this is the kind of stuff I love learning about). Then the filter mixes even more. For something like a nature trail, it's even ok if the stones and smaller weeds move into edge of the path. That's the way it would be in reality. Stewart, I agree, from looking at your file I wouldn't expect a problem. Just don't know if its a bug or limitation of the math formulas. Either way, I'm really glad to know about it now, instead of in the middle of some big project with a tight deadline.