We measured the throughput of high resolution mode of DIS. We were not doing accurate spectrophotometry, the numbers quoted here may only be accurate to 10-20 %. The throughput peaks at 13% and 8% in blue and red sides. The red side of the high resolution mode is about 50% less sensitive than the blue side. And combining with the fact that the red chip of DIS is more noisy, it makes getting decent spectra on red relatively difficult. The throughput is also considerably lower than that of low resolution mode (which peaks at 17% and 15% in blue and red), and somewhat lower than that of med mode (which peaks at 16% and 8%). ========================================================== Here are the numbers: =========================================================== Blue : central wavelength=4950, coverage ~4535-5365 4604 0.094 4735 0.118 4825 0.125 4914 0.129 5067 0.129 5145 0.121 5263 0.097 Red : central wavelength=6325, coverage ~5800-6850 5840 0.043 5980 0.046 6140 0.064 6290 0.077 6436 0.064 6530 0.063 6670 0.069 6790 0.063 -- Xiaohui Fan Princeton University Observatory Peyton Hall Princeton, NJ 08544 email : fan@astro.princeton.edu tel : (609) 258-5153 (O) (609) 716-0480 (H) APO APO APO APO APO Apache Point Observatory 3.5m APO APO APO APO APO This is message 45 in the apo35-dis archive. You can find APO the archive on http://www.astro.princeton.edu/APO/apo35-dis/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-dis@astro.princeton.edu APO APO APO APO APO APO APO APO APO APO APO APO APO APO APO APO APO