Nightly General Operations

See also the Curtis-Schmidt Telescope Operations Guide on the PreCam Users' Guide page.

Directory and File Nomenclature (subject to change):

  1. Store each night's data in their own directory named by the night's MJD (see the Night Logs page for the list of MJDs in September). E.g., the data for the night of 2010-09-15 UT would be MJD55454. Data taken that afternoon would also go into that night's data directory (even though, strictly speaking, the afternoon data would be observed before UT midnight).

  2. Images would have the following nomenclature, where MMMMMMMMM is a running ID provided by SISPI: (HA!- we have to learn how to set these!)

Afternoon Tasks:

During this part of the year, dinner starts at 5:30PM. Therefore, you probably should start taking afternoon

calibration exposures (biases, dome flats, darks) no later than about 2:30PM in order to finish up before heading down to

dinner.

  1. Turn off vacuum pump (???) using these instructions (link to be added) and following all ESD protocols. Only if requested to by Steve.

  2. Obtain a set of 25 bias frames (every afternoon). How do we script this?

  3. Point the telescope to the flat field screen and obtain a set of 10 dome flats in each filter (every afternoon) with the following exposure times (values to be filled in during commissioning): Can we do this during daytime?

    • g-band: 15 sec (yields ~ 34,000 ADU)

    • r-band: 20 sec (yields ~ 25,000 ADU)

    • i-band: 25 sec (yields ~ 30,000 ADU)

    • z-band: 15 sec (yields ~ 30,000 ADU)

    • y-band: 25 sec (yields ~ 30,000 ADU)

  4. Obtain a set of 10 dark frames for each of the following exposure lengths. This is a pretty long exposure sequence. Therefore, one can alternate, doing the (10-sec, 30-sec, 60-sec, 100-sec) darks one afternoon and the 300-sec darks the next afternoon. In addition, it is safe to start the darks and head down to the dorms for dinner. If we can script these!

    • 10 sec

    • 30 sec

    • 60 sec

    • 100 sec

    • 300 sec

  5. Copy the afternoon's data to the staging area on the Brazil Portal via FDT. See http://twiki.linea.gov.br/bin/view/Documentation/FdtTransfer and consult Leandro Martelli (martelli_at_linea.gov.br) for help.

Twilight/Early Evening Tasks:

Since we don't plan on taking twilight flats, there is no rush to get back up to the Curtis-Schmidt just at sunset. If you get back to the Curtis-Schmidt about 15 minutes after sunset, that should be adequate. (In early-September, sunset is around 6:35PM; in late-September, sunset is around 6:50PM.)

  1. Check the sky -- is it photometric? Note sky conditions in your manual log text file for tonight's Night Log.

  2. When you get back to the dome, make sure any data transfers are completed (if you started any in the afternoon).

  3. Go up to the observing floor and do a walk around of the telescope. Make sure TelOps has set it up correctly (they should, they're good). If you have to open the telescope, plan an extra 10-15 minutes to do so.

  4. Verify the clocks are correct.

  5. Use a bright star near zenith (mag < 3) to refine the pointing of the telescope. Due to the large gap between the two PreCam CCDs (about 1.6 armin in width!), it may make sense to check the pointing with a bright globular cluster instead. E.g, for September, the globular cluster NGC 6809 (a.k.a. M55) at RA=19:39:59.40, DEC=-30:57:43.5 (J2000.0), at an exposure time of 60 sec, is a good choice.

  6. Focus the telescope?

    • [From Darren DePoy:] "The focus is under computer control remotely from the control room (I think Kyler has software for SISPI to communicate with the focus mechanism as well). Although I expect that the focus should not change very much night-to-night, a nightly check is certainly worthwhile. Perhaps PreCam will have the ability to take focus frames? I also expect that there will be minimal focus shift between the DES filters. Again, however, that will be worth checking..."

    • [From Pat Seitzer:]

    • a. for final focus determination, change the focus by 25 units (25 microns) or less in your focus sequence.

    • b. the focus changes by -17.4 units per deg C. As the telescope cools during the night, the focus will increase. (This value was determined with 2.318 arcsec pixels, a more precise value could be determined with the smaller pixel cameras.)

    • c. the telescope temperature is displayed on the LED display on the panel next to the microphone downstairs.

    • d. with the old secondary, there was evidence that the focus depended on telescope position in the sky. No information on this secondary.

  7. Check the sky again -- is it photometric? Note sky conditions in your manual log text file for tonight's Night Log.

  8. Download the PreCam ObsTac list for the night, and feed it to the observing script.

  9. Start the observing script at the end of nautical (12-deg) twilight -- about half an hour before the end of astronomical (18-deg) twilight in September.

During Night:

  1. Keep an eye on sky conditions with RASICAM and TASCA (if they are available), and note the sky conditions in your manual log text file for tonight's Night Log.

  2. Even if RASICAM and TASCA are available, it is useful to go outside and check sky conditions every hour or so throughout the night and note the sky conditions in your manual log text file for tonight's Night Log. (Note that it can take up to 15 min to dark adapt.)

  3. If conditions change, stop the observing script and either:

    • download a new PreCam ObsTac list, feed the new list to the observing script, and restart the observing script (if conditions are good enough to continue observing), or

    • close the dome (and perhaps run some in-dome periodic tests described on the Commissioning and Periodic Tests page (if conditions are not good enough to continue observing).

End of Night Tasks:

  1. Observe until the beginning of nautical (12-deg) twilight, which is about half an hour after astronomical (18-deg) twilight in September.

  2. Shut down and stow telescope.

  3. Turn on vacuum pump (???) using these instructions (link to be added) and following all ESD protocols.

  4. Fill out the CTIO end-of-night form (only accessible from CTIO).

  5. Make any final additions to your manual log text file and attach it to the Night Logs page.

    • If you feel up to it, also add a link to the attached manual log text file to the appropriate row in the table on the Night Logs page.

  6. E-mail your manual log text file to the des-precam-obs mailing list (des-precam-obs@listserv.fnal.gov).

  7. Save the CTIO Environmental Page to a PDF or JPEG file and attach it to the Night Logs page.

    • If you feel up to it, also add a link to the attached PDF or JPEG file to the appropriate row in the table on the Night Logs page.

  8. If RASICAM is available (and if you feel up to it), include a link to that night's RASICAM movie to the appropriate row in the table on the Night Logs page.

  9. If RASICAM is not available but TASCA, save the TASCA red animated GIF and attach it to the Night Logs page.

    • If you feel up to it, also add a link to the attached animated GIF file to the appropriate row in the table on the Night Logs page.

  10. Start an FDT transfer of the night's data to the staging area on the Brazil Portal.

  11. GET SOME SLEEP! The madness will start again all too soon.