For those experiences in using DIS far into the red... I have some time next week for spectroscopy of the Ca triplet around 8500A using DIS in high res mode. I am looking for some advice on how to best deal with the fringing problems, e.g. in terms of which calibration or flats to take to remove as much of the fringing as possible, and methods on how to do that. thanks, Rene -- Rene Walterbos Astronomy Department New Mexico State University rwalterb@nmsu.edu APO APO APO APO APO Apache Point Observatory 3.5m APO APO APO APO APO This is message 924 in the apo35-general archive. You can find APO the archive on http://www.astro.princeton.edu/APO/apo35-general/INDEX.html APO To join/leave the list, send mail to apo35-request@astro.princeton.edu APO To post a message, mail it to apo35-general@astro.princeton.edu APO APO APO APO APO APO APO APO APO APO APO APO APO APO APO APO APO