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OBSERVING: A RECIPE

1. Log in, initialise software.

   At observer's console:

   SI < initials> ,< account number> ,< account number> (2.2.1)

   ADAM (2.2.1)

   and follow prompts. Note that it is most efficient in terms of observing time to put data to DISK only, and save it on TAPE later, using FITSOUT.

2. Instrument hardware setup OK?

   Cryostat filled and cold? (1.1.2)

   Correct filters, filter wheel, optical thicknesses (1.5.1)

   Chip orientation correct? (1.6.1)

   Telemetry OK? (2.3.6)

3. Calibration fields

   Get BIAS, DARK frames (1.4.1), (1.4.3), (2.3.17)

   Get flat fields (reddest first at end of night, last at start) (1.4.2), (2.3.16)

   Repeat later in the night

4. Telescope set up OK?

   Telescope pointing checked, SNAFU? (1.5.2)

   Finder offset zeroed? (1.5.2)

   Telescope and autoguider in focus? (FOCUS, SETFOCUS, SETGDFOCUS) (1.5.3)

5. Set telescope to object position.

6. Set position angle required.

   Adam:> ROTPOS < deg> (3.1.3)

7. Set filter required
   • For standard broadband wheel

     Adam:> FILTER < abbrev> (options are UBVRIZ) (3.2.1)

   • For other filters, set up software using WHEEL command, follow prompts. Then

   Adam:> FILTER < abbrev> (where the abbreviations correspond to the WHEEL assignments)

8. Check positioning, exposure required with a short exposure using

   Adam:> GLANCE < sec> (2.3.1)

   This run can be saved with

   Adam:> KEEP (2.5.4)

9. If autoguiding required (recommended for exposure times > 300 sec), find a guide star:

   Beamswitch A (1.6.2)

   Grinnell Select Guide Star (1.6.2)

   Beamswitch normal or enter RA/Dec on x/y coords

   Lock on the autoguider.

10. Make the real exposure:

    Adam:> RUN < sec> (2.3.2)

    This command makes the exposure, reads out the chip, displays the image on the LEXIDATA with auto-scaling, and saves the image file on disk, tape or both, depending on the option chosen. Useful commands during RUN are RUNSTATUS to tell you how long to go; STOP, which terminates and saves normally, just as if requested time had expired; ABORT, which closes the shutter and loses the data, and TIME < sec> which resets the requested exposure time.

11. To examine the data (best done from the point of observing efficiency after the next run has been started), use

    Adam:> PHOTOM (2.4.3)

    Follow instructions/indications on the LEXIDATA and the joystick box. To display and examine other runs:

    Adam:> DISP R< run number>

    Some on-line analysis is available; see 2.7. For general file-handling, see 2.5.

12. At the end of the session (unless the TAPE option was selected, section 2.5.10, write out data files to tape using

    Adam:> FITSINIT (follow prompts) and (2.5.11)

    Adam:> FITSOUT (follow prompts)

    Make your data safe and secure peace of mind by

    • using VERIFY option on FITSOUT, and
    • dismounting the tape from the deck and removing the write ring.

    Place completed D-tapes in the tray to be copied to produce your C-tape.

    It is strictly forbidden for observers to take D-tapes from the mountain.

13. At the end of the session, sign off:

    Adam:> SHUTDOWN (2.2.4)

    and after system messages,

    SO (sign off)

14. At the end of the observing session, check that the cryostat is refilled with liquid N. (Appendix C)