APO 3.5m User's Committee Phone Conference August 4, 2003 Attending: Ed Turner, Alan Uomoto, Bruce Gillespie, Mike Shull, Michael Strauss, Russet McMillan, Russell Owen, Karl Glazebrook, Jon Holtzman, Al Harper, Chris Stubbs Absent: Don York, Bruce Balick, Rene Walterbos Agenda: Status of summer shutdown The Telescope User Interface Telescope focus responsibility News on instruments, etc. *********Shutdown: Gillespie: The following are highlights among the many tasks being done: Tertiary has been realuminized. John Barentine has been working on NIC-FPS at Colorado Craig Loomis and Russ Owen have been working on TUI (see below) Two of the three DIS grating tilt motors have been replaced (they were missing and adding steps) The primary has been washed Work is on-going on the primary mirror supports and the secondary actuators Work is on-going to rebuild the telescope drives, including the rotator. The rotator now much smoother than before. It will take an extra week to put it all together, mostly because of the drives, so some observers will lose telescope time. Restarting on the sky always takes a night or two of engineering on the sky, so it will depend on the weather in late August. It has been quite a dry summer (bad news for forest fires); the monsoon has not yet begun... Given the on-going problems with the telescope drives, it was suggested that we have two sets of them, so that one is always available as a spare. This has been considered; it would cost an estimated extra $120,000 to do so. It is not high enough priority on the CIF budget at the moment. We are seriously looking at redesigning and replacing the drive boxes, including having five built (3 in service and two as spares). In-house estimates of the total cost are in the $50-100K range. Mike Carr of Princeton came out to the site and gave DIS a mechanical once-over, and said it looks in very good shape (other than the grating tilt motor change mentioned above. A small number of new cracks in the hex-cell ribs primary mirror, which were not present two years ago, have been seen. The good news is that they are few and tiny, and the old cracks have have not grown at all in several years. These new cracks show up where spreader bars are glued onto the sides of the hex cells. They are probably a consequence of the original epoxy glueing job. To fix these would involve substantial risk, downtime, and expense. We will continue to watch and hope that things don't get worse.... ***********Telescope-User Interface (TUI)********** This is the new Python-based replacement for Remark that Loomis and Owen are developing. They have been working particularly hard over the shutdown. As reported earlier, this will require that each ARC institution have a modern version of Python installed at their site. Seethe web site http://rowen.astro.washington.edu/TUI for details. At the moment, one can use TUI to take exposures with the echelle, DIS, and GRIM, and set the DIS configuration. On the task list are: -Image display -Widgets for focus -User catalogs of objects -Echelle and GRIM configurations -SPICAM exposures (should be easy) Note that the SPICAM command-line interface will still exist. TUI will support scripting, and should allow us to use the DIS slit viewer and the guide camera as well. ***********Telescope focus: who's responsible? There has been a fair amount of confusion and controversy over the question of who is responsible, the observer or the Observing Specialist (OS) to keep an eye on the telescope focus, and to correct it if necessary. This debate arose after some unfortunate recent incidents (under unusual conditions of rapid temperature changes, I believe) in which data were taken with the telescope delivering doughnuts. Russet McMillan says that the OS should have a large chunk of the responsibility of keeping an eye on the focus, but admitted that all the OS don't necessarily agree with her. The OS has the advantage of access to the guider images, which the remote observer can't easily access (soon to change with TUI; see above!). Jon Holtzman emphasizes that the ultimate responsibility is with the observer; they are the ones who are responsible for the scientific quality of the data. Having said this, getting input from the observing specialist is definitely very welcome! Chris Stubbs articulated three issues in the debate: The responsibility for the scientific integrity of the data rests with the astronomer, with information from the OS. We need to make sure that all OS are clear on how to monitor focus, and that there is a common set of well-communicated expectations. Clarity: Where do these responsibilities reside? Are the OS actually responsible for monitoring the focus, even if the observer has the responsibility to declare that we need to refocus? All agreed that if the OS notices that the focus appears soft, this should be communicated to the obserer. There are programs where very high-quality focus is a premium, in which case there needs to be communication between the observer and OS to this effect. A solution: some sort of autofocus? Use information from slit viewer/guider together with IDL code to determine the error in the focus, and use it to suggest a new focus. We discussed different ways that this might be implemented. Russet: A consensus: -Let's improve communication between OS and observers. -A certain amount of responsibility of monitoring image quality lies with the OS. -But overall responsibility of the image quality lies with the observer. Needless to say, this will be the subject of further discussion to clarify this and other issues of OS vs. astronomer responsibility. If you have thoughts/input, please talk with your User Community representative. *********************News on instruments************************ There is good news and bad news from the NSF. The good news is that the proposal to fund various aspects of NIC-FPS was approved. The bad news is that the proposal to fund the near-IR spectrograph to be built at JHU was not successful. The worse news is that Alan Uomoto is leaving us (and JHU) to take a new position with the Magellan project in Pasadena. We wish him the best of luck, and will miss him. Mike Shull reported that NIC-FPS is progressing well, with Jim Green now as PI. They are now working on integrating the optics and testing the dewar. Last month's minutes are approved. Next meeting, September 15, 11:30 AM Eastern time. APO APO APO APO APO Apache Point Observatory 3.5m APO APO APO APO APO This is message 687 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