Hi, What is the max Sieve tool (Post Classification) Group Min Th parameter with no error in output? I tried Group Min Th (690) and Number of Neighbors 8. It seems that Group Min Th parameter doesn't work. It sieve the class edges even if the pixel group are 1 million pixels. It seem sieve tools divides classification image into blocks and looks only into this blocks for the paramiters. Please explain me how the sieve tool works. Cheers, Jevgenijs