Hello all, Last month we received two new gratings for DIS -- the B400 and R300 gratings described in Jon Holtzman's message at http://www.astro.princeton.edu/APO/apo35-general/msg.964.html . We have mounted and characterized these gratings, and they both look very nice. The blue one gives a modest improvement in throughput and a slightly higher resolution than the old blue low grating, and the red one has distinctly better throughput along with a bluer blaze (good for Halpha) compared to the old red medium grating. Each grating provides full spectral coverage from the dichroic cutoff to the blue or red limit of the spectrograph. The B400 and R300 gratings will now become the standard lower-resolution setup for DIS. If observers request low resolution or blue low/red medium in their proposals or setup emails, we will assume they want the new gratings UNLESS there is an explicit request for the older ones (for example, to match earlier data). So please be specific in your requests. Note that the old blue medium (B600) grating has been removed from its mount for some measurements. We are considering whether to retire this grating and would like to hear from any observers interested in working with it in the future. The grating does have a very blue blaze wavelength and therefore might be useful to observers interested in features near the blue cutoff of the spectrograph; however, the grating has suffered some damage in recent years and is considered somewhat expendable. If anyone wishes to use this grating, let us know as soon as possible. The high resolution gratings described in Jon's message have not been delivered yet. Like the new lower-res gratings, they will be tested and characterized thoroughly before they become the default. Russet McMillan. APO APO APO APO APO Apache Point Observatory 3.5m APO APO APO APO APO This is message 978 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