Stewart, it looks like we cross-posted. But, yeah, what you're showing is what I tested, and made me realize there is a ratio problem. If you reduce the cherry tree in comparison to the terrain, it starts to work (or, if you increase the terrain in comparison to the cherry tree... same result). Anyways, it sounds like you understand about the ratios, so you know the work-around. Rickcz3, I like what you have going with only one big tree. Looks like everything is exactly what I'm hoping to do from this thread. I'm not sure yet if I understand what you're saying about where black meets white, since it's a gausian blur. Can you post a pic that shows the filter in use?