So the amount of filtering is determined by the mask-which is greyscaled (mask as image). Very neat. I sure am glad that I have this group to straighten me out LOL. I have to thank Deanna though, for broaching this subject in the Bryce ng to begin with. I'd looked at this in the Bryce manual but hadn't tried it and Deanna's post got me interested. Deanna, Spike has helped me in the past--I KNEW he would come through --VBG. A new 'trick' learned. smile Diane