This is an important issue. If it would be helpful, although clearly only a psychological ploy, we could easily list a much earlier time than -12 deg twilight as the start time on the observing schedule. Ed Turner APO APO APO APO APO Apache Point Observatory 3.5m APO APO APO APO APO This is message 619 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