Hello, I would like to use the sigma_filter.pro on an image in IDL 7.1. Im a new user and I dont understand how the calling sequence works. The documentation of the filter says that the calling sequence is: Result = sigma_filter( image, box_width, N_sigma=(#), /ALL,/MON ) Can someone help me? I try it in IDL command Line without any success. Thank you, Max Url of the sigma_filter.pro http://astro.uni-tuebinge..._filter.html#IDLLAB8