2MASS Operations Manual

Index

Telescope start up...

Telescope operations...

Filling the camera with LN2
Using the Pine Email system
Removing the previous nights data tape
Rebooting the NI2MASS/SI2MASS computers to DOS mode
Purging the previous nights data
Booting the 2MASS camera
Checking the camera shutter position
Removing the LN2 fill tank
Taking the evening twilight flats
Aligning the telescope with a reference star
2MASS data taking operations
Eyeball quality of the current sky conditions
Morning alignment star check
Taking the morning twilight flats
Taking the Dark Frame

Telescope shut down...

Writing a data tape

Appendix A - General Observing Notes

Appendix B - Troubleshooting the system

All Drives not present
Camboot failure - LFI lights not blinking correctly
No stars present on Real Time Display
Camboot timeout
Large error signal on oscilloscope
N2MASS / S2MASS computer crashes
NI2MASS / SI2MASS computer crashes
Power failure in the observatory

Appendix C - Primary mirror cleaning

Appendix D - Booting/Re-booting the system

N2MASS / S2MASS
NI2MASS / SI2MASS
TCS

Appendix E - Camera LN2 Fill procedures and LN2 Safety

Appendix F - Replanning the night

Appendix G - Oscilloscope settings

Appendix H - Closing due to weather and snow & ice removal

Appendix I - Lightning Procedures

Appendix J - Locations and photographs of items in the 2MASS observatory

Start Up

Telescope start up...1 hour before start of observing.

  1. Review Appendix A.

  2. Turn on the N2MASS / S2MASS, NI2MASS / SI2MASS, and TCS computers & monitors and confirm that the computers are running. (you may have to press the shift key to exit the screen saver powerdown mode.)

    • If any of the computers are not running see Appendix D.

  3. Turn on the oscilloscope.

    4. Filling the camera with LN2

  4. Start filling the Telescope camera dewar with LN2.

    5. WARNING!!!

    If the camera takes more than 30 minutes to fill,
    STOP THE FILL AND CALL UMASS (ERIC HOWARD)!

  5. After the camera has been filled, check for excessive ice buildup on the camera dewar fill and vent port. Call UMASS if excessive.
    6.

  6. (South only) Weather conditions permitting, open the control room door and turn the control room fan on full.
    7.

  7. At the N2MASS / S2MASS computer login prompt, type: ops
    8.

    • The N2MASS / S2MASS computer will ask you for a password, enter the 2MASS login password that was provided to you.
      •

  8. On the N2MASS / S2MASS computer type: startx

    • The N2MASS / S2MASS computer will now start X-Windows.
    • It will open a X-Term window.
    • It will turn on the screen clock display.
    • It will place a Netscape icon on the screen.

    Using the Pine Email system

  9. In the X-Term window type: pine
    10.

  10. On the N2MASS / S2MASS in the X-Term window type: obs ###, where ### is the night number.
    11.

    Observers Log Screen (EMACS)
    N2MASS / S2MASS computer
    ****************************************************************

    Did you purge last nights data ???????????????????
    Run newlog ???????????????????

    ****************************************************************




    Observers Log for Night #night# (#ut date#  UT)

    Observer:

    Weather Conditions:

    Eyeball quality estimates:

    Notes:

    GMT    Scan         Comment

  11. In the observers log, On the N2MASS / S2MASS computer, record the following information where specified:
    12.

  12. If the dome was opened earlier (to allow additional dome cooling time), record in the observers log, below 'GMT Scan Comment', the time that the dome was opened and that the dome fans were turned on. The dome SHOULD NEVER be opened when direct sunlight can fall on the primary mirror.
    13.

  13. Record in the observers log, below the 'GMT Scan Comment', the time the camera was filled with LN2 and the time required for the fill.
    14.

  14. In the dome, clean dust off from the camera dewar window using a blow bulb.
    15.

  15. Record the camera array temperatures (ct) and time in the observers log. These can be read from the red LED display inside the dome. Also record the camera vacuum. This can be read from the digital guage mounted on the telescope(allow the guage a minute for the readings to settle and turn the guage off when not in use.)
    16.

    Removing the previous nights data tape

    The next 5 steps should be done IF survey data was taken and data tapes were written the previous night.

  16. Confirm that the NI2MASS / SI2MASS computer wrote the data tape correctly.
    17.

  17. Remove tapes from DLT tape drive and close the tape doors.
    18.

    • On the DLT tape drive, press both unload buttons and wait for the green "operate handle" lights before lifting the handles to remove the tapes. There should be very little resistance felt when removing the tapes, if there is see Appendix B.
      •

  18. Write protect the DLT tapes by sliding write protect mechanism on the tape until the orange flag appears.
    19.

  19. Label both DLT tapes using the labels that were filled out the previous nights shutdown or from the information provided on NI2MASS / SI2MASS screen. Also write N2MASS or S2MASS on the label (depending on location).
    20.

  20. Store one tape copy in observatory archive, Place the other data tape on the designated shelf to hold for shipping.
    21.

    Booting the NI2ASS/SI2MASS computer into DOS mode

  21. Turn off the DLT tape drive
    22.

  22. On the NI2MASS / SI2MASS computer, simultaneously press and then release the following keys: Ctrl-Alt-Delete and wait for the LILO prompt. DO NOT USE THE RESET BUTTON ON THE COMPUTER TO REBOOT WHEN IN LINUX. This will reboot the NI2MASS / SI2MASS computer.
    23.

  23. On the NI2MASS / SI2MASS computer, at the Boot: prompt type dos There is a 30 second delay before the computer automatically boots into LINUX mode. If it does so, just follow the above step again to reboot the computer.
    24.

  24. The NI2MASS / SI2MASS computer should now boot up in MS-DOS mode. After some system initializations, it should stop at a command prompt. (C:\CURRENT:> ).
    25.

  25. On the TCS computer type TCS at the DOS command prompt and follow the on screen prompts to initialize the telescope control system.
    26.

    Purge the previous nights data

    Warning!!!

    The next command WILL ERASE all of the previous nights data.

    BE CERTAIN THAT ANY TAPE BACKUP HAS FINISHED CORRECTLY BEFORE ERASING THE DATA.

  26. At the command prompt (C:\CURRENT> ), on the NI2MASS / SI2MASS computer, type: purge
    27.

  27. The NI2MASS / SI2MASS computer will ask: 'Do you really want to purge the data on the SCSI drives?[Y,N]?'

  28. At the command prompt, on the NI2MASS / SI2MASS computer, type: chkpurge

    29. Purge command
    NI2MASS / SI2MASS computer
    **********************************************
    * Watch for "Invalid drive specification"!!! *
    **********************************************

    Volume in drive D is DATA
    Volume Serial Number is xxxx-xxxx
    Directory of D:\

    File not found
    Press any key to continue ...



    Volume in drive E is DATA
    Volume Serial Number is xxxx-xxxx
    Directory of E:\

    File not found
    Press any key to continue ...

    .
    .
    .

    Volume in drive O is DATA
    Volume Serial Number is xxxx-xxxx
    Directory of O:\

    File not found
    Press any key to continue ...

    Drives D through O should all be present in the system, if not then see Appendix B on troubleshooting the system.

  29. On the NI2MASS / SI2MASS computer type: script
    30.

    • The 'script program' should now start on the NI2MASS / SI2MASS computer.
      •

  30. From the script menu on the NI2MASS / SI2MASS computer, select newlog.sct (option #5) by entering the 5 key on the keyboard.
    31.

    • This command only needs to be done once at the start of the night, if the computer should lock up during the night, another 'newlog.sct' is not necessary.
    • In the observers log you can now delete the two questions asking 'Did you purge last nights data?' and 'Run newlog?'.
    • Record in the observers log that the computer has been purged, chkpurged, and the newlog has been run.
      •

  31. On the NI2MASS / SI2MASS computer, select view.sct (option #7) by entering the 7 key on the keyboard. The RA, Dec, Tel Temp, should match what is displayed on the TCS computer screen. (the RA may be changing on the TCS screen, but not on the NI2MASS / SI2MASS computer). If the values do not match, then see appendix B, NI2MASS / SI2MASS to TCS communication problems.
    32.

    Booting the 2MASS camera

  32. (South Only) Turn on finder scope (turn on power strip in the dome and monitor in the control room).
    33.

  33. On the NI2MASS / SI2MASS computer, select camboot.sct (option #9) by entering the 9 key on the keyboard.

  34. Follow the prompts on the NI2MASS / SI2MASS screen for booting the camera electronics.

  35. On the NI2MASS / SI2MASS computer, select real time display (option #4) by entering the 4 key on the keyboard.
    36.

    The camera electronics MUST be operating for at least 5 minutes before taking any data (Dark frames, Twilight Flats, or Survey data).

    Checking the camera shutter position

  36. The shutter should have been left fully open from the previous night's observations. This can be roughly checked by looking at the shutter pull wires on the camera. The wire that is the longest will represent the state that the shutter is in.
  37. With the dome CLOSED and the incandescent dome lights on LOW perform the following to confirm that the shutter is fully opened.
    38.

    Removing the LN2 fill tank

    30 minutes before starting twilight flats:

    The following procedures should be performed approximately 30 minutes before the start of observing, pending weather conditions.

    If NO observations are going to be taken for the night, due to weather or other circumstances, then proceed to the telescope shut down section.

  38. Remove the LN2 storage tank from the camera. See Appendix E for tank removal instructions.
    39.

  39. (South only) Shut the control room door and turn down (not off) the control room fan.
    40.



    WARNING!!!

    REMOVE ALL OBJECTS NEAR THE TELESCOPE, ESPECIALLY THE LADDERS AND LN2 STORAGE DEWARS AT THIS POINT.



    WARNING!!!

    Only use the high speed slew when you are physically observing the telescope.

  40. Read all of the steps listed below before actually running start_up.sct, NOTE: The steps listed below need to be done while going through the start_up script. Start_up script will not necessarily prompt you to do all of these steps!

    After reading the steps below, on the NI2MASS / SI2MASS computer, select start_up.sct (option #16) by typing 16 on the keyboard and follow the on screen prompts. Direct sunlight should never strike the telescope!

    NOTE: The dome rotation controler is the black box inside the dome on the wall next to the metal cabinet.

    NOTE: The Telescope Drive Interlock is the red box on the wall in the control room.

    • Pending weather conditions outside open the dome perform the following functions:

      1. If the dome is not in the "home" position, where the electrical outlets can easily be accessed, see Appendix B for the procedure to "home" the dome.
      2. (North only) Turn the Air Conditioning OFF in the dome.
      3. Close the outside door, if open.
      4. When prompted by the start-up script, using the step ladder, plug in the electrical cord for the dome slit/flap motor.
      5. Start opening the dome slit using the control marked 'S' or 'Slit'. The dome slit will automatically shut off.
      6. After starting the slit opening, wait about 1 min then start opening the dome flap using the control marked 'F' or 'Flap'.
      7. Turn the control, marked 'F' or 'Flap', off when the flap is horizontal.

        8. WARNING!!! THE DOME FLAP DOES NOT AUTOMATICALLY SHUT OFF.

      8. After the slit and flap are fully opened, turn off the control marked 'S', unplug the electrical cord, and stow the cord on the motor carriage.
      9. Turn on the dome exhaust fan to the low setting.
      10. (North only) Turn on the telescope mirror cooling fans.
      11. Move the step ladder back against the wall, where it belongs.
      12. Note the time that the dome was opened and record this in the observers log.
      13. Follow the remaining prompts on the NI2MASS / SI2MASS computer to complete the startup.sct.

    • The dome controller power MUST BE OFF whenever the electrical cord to open the dome slit/flap is connected to the outlet.
    • The RED crash buttons are located on the wall for emergency shutdown of the telescope drives.
    • The RED crash buttons are reset by turning the button clockwise until the button pops out.
    • Press the F9 key on the TCS computer before resetting the drive interlock.
    • When executing the start up procedure, be prepared to quickly shut down the drives, using the RED crash buttons, if the telescope starts slewing unexpectedly.
    • There may be a significant pause while the computer moves the secondary through its focus range. Watch that the Foc: value on the TCS computer screen, be sure it does not get stuck cycling between two values, If it sticks or the Focus Limit Switch lights come on, see Appendix B.
    • Now re-read all of the above steps to make sure that you understand the procedure.

  41. Record in the observers log Temp value (tt) and Foc: value (ZFoc) as read from the TCS computer screen. The telescope should now be in the stow position (pointing at the zenith).
    42.

  42. On the NI2MASS / SI2MASS computer, select real time display (option #4) by entering the 4 key on the keyboard.
    43.

  43. On the NI2MASS / SI2MASS computer, press the j key on the keyboard.
    44.

  44. On the NI2MASS / SI2MASS computer, press the s key on the keyboard.
    45.

  45. On the NI2MASS / SI2MASS computer, press the 5 key on the keyboard.
    46.

  46. On the NI2MASS / SI2MASS computer, press the x key to toggle the Background subtract on. A Bkgrnd Sub on should be displayed on the screen. (It may take a couple of toggles to get the 'Background subtract on' displayed.)
    47.

  47. On the NI2MASS / SI2MASS computer, press the x key once to toggle the Background subtract off. The Bkgrnd Sub on should be NOT be present on the screen.
    48.

  48. If there are curved images on the display the shutter is not fully opened. See the above section on checking the shutter position.
    49.

    Taking the evening twilight flats (Weather Permitting)

    5 Minutes before the scheduled start of twilight flats:

  49. On the NI2MASS / SI2MASS computer press the Esc key to get back to the 'script menu'.
    50.

  50. On the NI2MASS / SI2MASS computer, select auto_mode.sct (option #1) by pressing the 1 key on the keyboard.
    51.

  51. On the N2MASS / S2MASS computer, left click with the mouse on the scheduler's title bar to bring it to the front.
    52.

  52. On the N2MASS / S2MASS computer, in the scheduler's window, press the M key (mode change) and then press A key (Almost-Remote Mode) to set the scheduler into 'almost remote mode'.
    53.

  53. On the N2MASS / S2MASS computer, The scheduler window should report that the RS-232 like checks out OK. If not the NI2MASS / SI2MASS computer is probably not in 'auto_mode' from the step above.
    54.

  54. Before starting evening flats, make sure the doors are closed and the lights have been turned off.

    At the scheduled time to start taking flats.

  55. On the N2MASS / S2MASS computer, in the scheduler window, move the highlight bar down to the first twilight flat.

    For the time being, we are skipping the evening dark frame.
    Observing should be started at the time specified on the scheduler, if not see Appendix F on replanning the night.

  56. At the UTC time that the scheduler schedules for the first twilight flat:
    57.
    • Press the H key and then press S key to highlight the desired scan and start the scheduled observing run.
      •

  57. When the real time display appears on the NI2MASS / SI2MASS computer, press the 7 key on the keyboard to place the small box on the real time display in the center of the upper left quad.
    58.

  58. On the real time display from the NI2MASS / SI2MASS computer, toggle (with the 'X' key) the Background subtract to ON. You should observe stars moving vertically on the real time display. If not, stop the scan on the N2MASS / S2MASS scheduler by pressing the S key then see Appendix B.
    59.

  59. On the oscilloscope a saw-tooth waveform should be observed. This is the signal going to the secondary on the telescope.

  60. On the oscilloscope a small amplitude random signal should also be observed. This is the error signal for either the Dec or RA axis (depending upon which signal line is plugged in to the channel).

    The settings for the oscilloscope are can be found in Appendix G.
    If the peak to peak height of the error signal exceeds 4 large squares, see Appendix B.

    61. During the break between the scheduled end of flats and the start of the first calibrator (~5 minutes):

  61. Turn off the dome exhaust fan. Open both of the doors in the dome leading outside, unless it is too windy to keep doors open.
    62.

  62. (North only) turn off the telescope mirror cooling fans.
    63.

  63. In the observers log note the time that the fans were turned off.
    64.

  64. After the dome exhaust fan is turned off, it should NOT be turned on again, unless there is a significant temperature differential (more than 2 deg. C) between the Tel Temp and HRing Temp. The telescope mirror cooling fans SHOULD NOT be on while data is being taken.
    65.

    Aligning the telescope with a reference star

  65. On the TCS computer's menu bar (located on the bottom of the screen):

    1. Press the Esc key.
    2. Move to the menu option called Motion and press the ENTER key.
    3. Check that the Paddle has a check mark beside it. If not scroll to the Paddle item and press the ENTER key to toggle the check mark ON.
    4. The telescope tracking must be turned on at this point, scroll to the Tracking item and press the ENTER key to toggle the check mark ON
    5. Move to the menu option called Source.
    6. Move to the menu option called PCF Catalog and then press the ENTER key.
    7. Move to the menu option called FK5 and then press the ENTER key.
    8. Move to the menu option called Position.
    9. Select Next or simultaneously press the CTRL and N keys.
    10. Select a star from the catalog list that is near the zenith (use the LST on the TCS computer to get an approximate RA value and a Dec value of the telescopes Latitude (+/- ~15 degrees). Try to choose a star that is near to the telescopes zenith value though. Page Up and Page Down will move through the list, the arrow keys will move in the list. Highlight the desired star and press the ENTER key to select it. Objects in RED cannot be selected. Note in the observers log which star # was selected and if the star is being used for a telescope alignment or as a telescope check alignment star.
    11. Move to the menu option called mOve.
    12. Select Next or simultaneously press the ALT and N keys.
    13. The telescope should now slew to the desired stars location.

      14. When the telescope is moving, the RA and Dec on the TCS computer should turn red.

    14. On NI2MASS hit the `ESC' key then "A" to get out of the real time display mode. Now select 12 (focus.sct) to get the camera electronics working (light blinking) and then 4 (real time display mode).
    15. On the NI2MASS / SI2MASS computer, press the j key on the keyboard.
    16. On the NI2MASS / SI2MASS computer, press the r key on the keyboard.
    17. On the NI2MASS / SI2MASS computer, press the 5 key on the keyboard.
    18. On the NI2MASS / SI2MASS computer, press the x key to toggle the Background subtract on. A Bkgrnd Sub on should be displayed on the screen. (It may take a couple of toggles to get the 'Background subtract on' displayed.)
    19. On the NI2MASS / SI2MASS computer, press the x key once to toggle the Background subtract off. The Bkgrnd Sub on should be NOT be present on the screen.
    20. The star should now be located in the field of view on the NI2MASS / SI2MASS computer's real time display. The star should also be visible on the finder monitor screen (note: The dome may obstruct the viewfinder.).

    21. With the star located on the real time display, use the hand paddle to position the star in the center of the small box on the screen. A magnified view of the small box is shown in the lower portion of the screen.

      22. Do NOT use the high speed slew (D + arrow keys on the paddle) when aligning the telescope to the star.

    22. With the star now located in the center of the Real Time Display, on the TCS computer, Move to the deClare menu and select Initial or simultaneously press the ALT and = keys then answer Y to initialize the telescope.

    23. On the TCS computer, press the ALT and N keys. The star should NOT move on the real time display.

    24. Repeat the Telescope Alignment a second time using a different start to double check that the telescope is properly aligned..

    25. On the TCS computer press the Esc key.

    26. On the NI2MASS / SI2MASS computer, press the 7 key on the keyboard to place the small box on the real time display in the center of the upper left quad.

    27. On the TCS computer simultaneously press the ALT and S keys to stow the telescope.

    28. If you wish, you may move the scheduler window on the N2MASS / S2MASS computer onto another virtual screen. Clicking it's title bar and drag it down to the bottom edge of the window, it should move onto the bottom virtual window.

    29. On the NI2MASS / SI2MASS computer, press the 'ESC' key and the select auto_mode.sct (option #1).

      30. WARNING!!!

      If you are not going to start observing right away, due to weather or other circumstances, ALWAYS STOW THE TELESCOPE by simultaneously pressing the ALT and S keys on the TCS computer.

    30. Continue to the Telescope Operations section.
      31.

    2MASS Data taking operations...

    The 2MASS telescope is a fairly automated system, however there are a few tasks that the observer still must perform during normal operation of the telescope. The principle tasks are to monitor the system and keep it operational, also the observer needs to monitor the outside weather conditions.

    If you are NOT starting on time, due to weather, see Appendix F on replanning the night.

    If weather does not permit observing for the entire night, skip to the section 'Shutting down'.

    WARNING!!!

    If you have to stop the scheduler for any period of time, ALWAYS STOW THE TELESCOPE by simultaneously pressing the ALT and S keys on the TCS computer.

    1. On the N2MASS / S2MASS computer, in the scheduler window, move the highlight bar down to the first calibrator tile.

      Observing should be started at the time specified on the scheduler, if not see Appendix F on replanning the night.

      Whenever starting or re-starting an observing run, you MUST always start with a series of calibrator scans, see Appendix F on replanning the night if necessary.

      Observations preferably should end with a series of calibrators, weather permitting of course.

    2. At the UTC time that the scheduler schedules for the first set of calibrator scans:
      3.
      • Press the M key and then press A key. The scheduler should report that the RS-232 line checks out OK. If not then the most likely cause is that the NI2MASS / SI2MASS computer is not in Auto-Mode.
      • Press the H key and then press S key to highlight the desired scan and start the scheduled observing run.
        •

    3. When the real time display appears on the NI2MASS / SI2MASS computer, press the 7 key on the keyboard to place the small box on the real time display in the center of the upper left quad.
      4.

    4. On the real time display from the NI2MASS / SI2MASS computer, toggle (with the 'X' key) the Background subtract to ON. You should observe stars moving vertically on the real time display. If not, stop the scan on the N2MASS / S2MASS scheduler by pressing the S key then see Appendix B.
      5.

    5. On the oscilloscope a saw-tooth waveform should be observed. This is the signal going to the secondary on the telescope.

    6. On the oscilloscope a small amplitude random signal should also be observed. This is the error signal for either the Dec or RA axis (depending upon which signal line is plugged in to the channel).

      The settings for the oscilloscope are can be found in Appendix G.
      If the peak to peak height of the error signal exceeds 4 large squares, see Appendix B.

    7. On the real time display from the NI2MASS / SI2MASS computer, toggle (with the 'X' key) the Background subtract to OFF.
      8.

    8. On the N2MASS / S2MASS computer, Sometime during each series of CALIBRATOR and SURVEY tiles, record the following information in the observers log:

      1. Time of current scan (in GMT).
      2. Scan # - Read from the NI2MASS / SI2MASS computer as files: x:{j/h/k}aaaabbb.rdo. 'x' is the drive that is currently being written to. 'aaaa' is the night #. 'bbb' is the scan #.
      3. Telescope temperature (tt=) - This is Tel Temp on the NI2MASS / SI2MASS temperature screen that pops up before starting the scan (you have to be quick). It can also be read as Temp: on the TCS computer.
      4. Headring Temperatue (ht=) - This is HRing Temp on the NI2MASS / SI2MASS temperature screen that pops up before starting the scan (you have to be quick).
      5. Air Temperature (at=) - This is Air Temp on the NI2MASS / SI2MASS temperature screen that pops up before starting the scan (you have to be quick).
      6. Humidity (h=) - This is Humidity on the NI2MASS / SI2MASS temperature screen that pops up before starting the scan (you have to be quick).
      7. The Focus value (foc=)from the TCS computer.
      8. Camera mean background levels (bkgnd=J,H,K) for J, H, and K Bands - aka Airglow. Use the pix mn values on the real time display screen AFTER at least 10 scans with the background subtract off.

        9. Also record these values if:

        • When the any of the bands background levels are changing significantly.
        • If the temperature is changing rapidly.

      9. Don't rely on the NI2MASS / SI2MASS computer for displaying the correct current status of the 'Bkgrd Sub'.
      10. Toggle the background subtract on/off with the 'X' key on the NI2MASS / SI2MASS computer.

      11. The real time display on the NI2MASS / SI2MASS computer should normally have the Background subtract left on (ie. stars visible).

        • The X key, on the NI2MASS / SI2MASS computer, will toggle it on and off.
        • The onscreen 'Bkgrd Sub On' indicator may not be displayed on the real time display, even though it may be on.
        • The Background subtract should ALWAYS be off when measuring background levels.
        • The small box on the real time display should be positioned in the middle of the upper left quadrant of the camera display. It can be positioned there by pressing the 7 key on the NI2MASS / SI2MASS keyboard.

      12. The outside Weather Conditions and Eyeball quality estimates should be recorded, in the observers log, at least once each hour. More frequently when the sky conditions are changing.

        'Eyeball' quality of the current sky conditionses

        Be aware that the telescope may move to a different part of the sky in the middle of a series of survey tiles.

      13. Below are the most common problems encountered during normal telescope operations.

        Camera time outs on real time display - see Appendix B, Troubleshooting.
        Airmass warning on scheduler - see Appendix F, replanning the night.
        Beyond telescope limits warning on scheduler - see Appendix F, replanning the night.
        Clouds & changing weather conditions - see Appendix H, Closing due to weather.

        14. Morning Telescope Alignment Star Check

      14. At the end of the last scan (Before Morning twilights) check the Alignment of the telescope using an FK5 star.
      15. On the NI2MASS / SI2MASS computer press the esc to exit the scripts auto_mode.
      16. On the NI2MASS / SI2MASS computer issue a focus (12) command.
      17. On the NI2MASS / SI2MASS computer issue the real time display (4) command.
      18. On the NI2MASS / SI2MASS computer press the 'j' key.
      19. On the NI2MASS / SI2MASS computer press the '5' key.
      20. On the NI2MASS / SI2MASS computer press the 's' key.
      21. On the NI2MASS / SI2MASS computer press the 'x' key.
      22. On the TCS computer go to the Source menu.
      23. On the TCS computer select the PCF Catalog.
      24. On the TCS computer select FK5.
      25. On the TCS computer move to Postion menu.
      26. On the TCS computer select Next.
      27. Now choose a star that is located near the Zenith. Also record the star # in the observers log.
      28. On the TCS computer move to Move menu.
      29. On the TCS computer select Next, this should slew the telescope to the selected FK5 star.
      30. On the NI2MASS / SI2MASS computer Wait for star to appear on Real Time Display
      31. On the TCS computer Press F5, this will zero out the difference values located on the TCS screen to allow us to tell how much the star is offset from where it should be.
      32. On the TCS computer press Esc on TCS (to get rid of menu pullup).
      33. On the NI2MASS / SI2MASS compute center star in zoomed box using the hand paddle.
      34. Record, in the observers log, the RA & DEC differences as shown on the TCS screen.
      35. On the NI2MASS / SI2MASS computer press the '7' key.
      36. On the NI2MASS / SI2MASS computer press the 'ESC' key.

        37. Taking the Morning Twilights (Weather Permitting)!

      37. At the end of the night the scheduler will halt before taking the morning twilight flats. If you took flats in the evening do not take them again in the morning. Typically we want to take twilight flats until the sun rises. This typically takes 6 to 9 scans. Direct sunlight SHOULD NEVER be allowed on the telescope.

        The Twilight flats should be taken at the end of the night as scheduled after the last set of calibrator tiles ONLY if they were not taken in the evening.

      38. On the NI2MASS/SI2MASS computer press the '1' key (auto_mode).

      39. At the scheduled time on the scheduler (N2MASS/S2MASS computer) highlight the first morning twilight then press the 'M' 'A' 'H' 'S' keys in that order to start the taking the morning twilight flats

      40. Record in the observers log the time and scan # for the first twilight flat. Also record the various temperatures and humidity for this scan.

      41. If the twilight flats have not finished and the sun has risen, Press 'C' on the scheduler to complete the current scan and then halt at the Dark Frame.

      Taking the Dark Frame

      A Dark frame needs to be taken when requested by UMASS. If no dark frame is to be taken, leave the camera shutter in the open position and skip to the Telescope Shutdown procedure.

      1. On the Camera attached to the telescope, GENTLY PULL the shutter wire marked CLOSE to close the camera shutter.

        The camera shutter will need to be closed a minimum of 5 minutes before the dark frame can be taken.

      2. On the NI2MASS / SI2MASS computer, Press the ESC key to exit remote mode, then press A to abort script.

      3. On the NI2MASS / SI2MASS computer, select the shutdown.sct (option #17) by entering the 17 keys and follow the onscreen prompts, EXCEPT:

        Do NOT turn off the camera power supplies.

      4. Turn off all of the lights in the dome, especially incandescent lighting. All doors should also be closed.

      5. By this time about 5 minutes should have passed, the dark frame can now be taken.

        If 5 minutes have not passed, you must wait until the camera shutter has been closed for at least 5 minutes before proceeding.

      6. On the NI2MASS / SI2MASS computer, select auto_mode.sct (option #1) by entering the 1 key on the keyboard.

      7. On the N2MASS / S2MASS scheduler, move the highlight bar down to the dark frame.

      8. On the N2MASS / S2MASS computer, in the scheduler's window, press the M key, then press the A key, then press the H key, and finally press the S key to start taking the dark frame.

      9. On the NI2MASS / SI2MASS computer, confirm that the shutter has been closed for at least 5 minutes.

        While taking Dark Frames, You should NOT go in or out of the dark dome.

      10. Record the time and scan # in the observers log for the dark frame.

      11. After the Dark frame is finished, Be sure to open the camera shutter again.

        You may turn the dome lights back ON, AFTER the dark frame has been taken.

        Telescope Shut down...

      12. Attach the LN2 storage dewar to the camera and start the LN2 Fill. Open the valve just enough so that the pressure relief valve doesn't chatter. LN2 WILL run out the pressure relief valve if the LN2 tank valve is opened too much. LN2 will run out of the MAIN vent when full. Be aware that the camera is NOT full if LN2 only runs out of the pressure relief valve. It normally takes about 10 mins to fill the camera. You may continue on with the procedures below while the camera is filling, but be attentive to turn the LN2 off as soon as the camera is full.
        WARNING!!!

        If the camera takes more than 30 minutes to fill,
        STOP THE FILL AND CALL UMASS (ERIC HOWARD)!

      13. Record the camera temperatures in the observers log.
        14.

      14. Record the camera vacuum in the observers log. It takes about 1 min for the vacuum guage to stabalize when first turned on. Be sure to turn the vacuum guage back off when finished taking the reading.
        15.

      15. On the N2MASS / S2MASS computer, Press the Q key to exit the scheduler. This will be done automatically if a Dark frame was taken.
        16.

      16. On the NI2MASS / SI2MASS computer, Press the ESC key to exit remote mode, then press A to abort script.
        17.

      17. On the NI2MASS / SI2MASS computer, select the end_program (option #0) by entering the 0 key and then answer y to really exit. This will exit the NI2MASS computer to the DOS prompt.
        18.

      18. Close both tape drive doors and turn on the DLT tape drive.
        19.

      19. Re-boot the NI2MASS / SI2MASS computer to LINUX mode by pressing the RESET BUTTON on the CPU. The computer will reset itself in about 60 seconds to LINUX mode with no user intervention.
        20.

      20. Turn the camera electronics off in the control room (LFI Control/Data Interface Box) AND the two power supplies in the dome.
        21.

      21. (South Only) Turn off the finder & video monitor.
        22.

      22. At the login prompt on the NI2MASS / SI2MASS computer, type: ops.

      23. The N2MASS / S2MASS computer will ask you for a password, enter the 2MASS login password that was provided to you.
        24.

      24. If ANY survey data WAS taken for the night, then a data tape will need to be written. If only a dark frame was taken, a data tape DOES NOT need to be written for the night.
        25.

        Writing a data tape

          To write a data tape:

        1. Press the unload button for each drive to release the tape drive door handles.
          2.

        2. Lift both handles on the tape drive.
          3.

        3. Fully insert a tape into each of the DLT tape drives and push handle down. The tapes should insert into the drive with very little resistance. If you feel excess resistance when inserting the tape STOP, remove the tapes, close the handles, turn the drive off and on, press the unload buttons and wait for 'Operate Handle' light, lift handles and try inserting the tapes again. If this does not solve the problem call UMASS (Eric Howard).
          4.

        4. Wait for the tape to rewind (stop spinning in the tape drive)

        5. On the NI2MASS / SI2MASS computer type: tdir.
          6.

        6. The NI2MASS / SI2MASS computer will display the date and amount of data that is to be written to tape. This information should be recorded on two tape labels. The word N2MASS or S2MASS (depending on location) should also be written on the tape label..
          7.

        7. In the observers log, record that a data tape was written in COMPRESSED format.
          8.

        8. On the NI2MASS / SI2MASS computer type:

          backup |& tee status

          to start the tape backup.

          This process may take several hours to complete and the tapes should start writing immediately (scan numbers scrolling on the NI2MAS/SI2MASS computer screen. If you do not see this call UMASS.

      25. Record in the observers log the time of fill and time required to fill the camera.
      26. This process should take 15 minutes or less (normally about 10 mins).
      27. See Appendix E for detailed LN2 filling procedures.
        28.

      28. Record the position that the dome ended the night in the log (Note if the upper arrow was aligned with either of the lower arrows and if not measure how far off it was and record this value in the log).
        29.

      29. After the camera has been filled, Record the fill time in the observers log and check for excessive ice buildup on the camera dewar fill and vent port. If ice buildup seems excessive contact UMASS for further instructions.
        30.

        LEAVE THE STORAGE DEWAR ATTACHED TO THE CAMERA.

      30. Power down the TCS computer by:
        31.

        1. Move to the shutDown menu and press the ENTER key.
        2. Press the ENTER key again for Auto shutdown.
        3. Press the ENTER key a third time to exit to a DOS prompt, sometimes the ESC key needs to be pressed to exit.
        4. At the DOS prompt, turn the power off on the TCS computer, don't forget to shut the monitor power off also!
          5.

      31. Make any final comments or notes in the observers log that need to be included.
        32.

      32. If this the end of your shift, leave comments at the bottom of the observers log that the next observer needs to be aware of.
        33.

      33. On the N2MASS / S2MASS computer, in the observers log, go to the 'Files' menu with the mouse and select 'save buffer' to save the observers log.
        34.

      34. On the N2MASS / S2MASS computer, in the open xterm window, type: cd logs to change to the logs directory.
        35.

      35. On the N2MASS / S2MASS computer, in the open xterm window, type: printsmall nlog.###, where ### is the night #. This will print out a hard copy of the observers log file and should be taped into the observers notebook.
      36. Confirm that the log has printed on the printer and is correct. On the N2MASS / S2MASS computer, in the observers log, go to the 'Files' menu with the mouse and select 'Exit Emacs' to exit the Emacs editor.
        37.

      37. On the N2MASS / S2MASS computer, in the open xterm window, type: (North) mail log < nlog.### or (South) mail log < slog.###, where ### is the night #.
        38.

      38. On the N2MASS / S2MASS computer, move the mouse pointer outside any open window and press and hold the left mouse button.
        39.

      39. Move the pointer to Exit Fvwm.
        40.

      40. Select Quit fvwm2 to exit X-Windows back to a LINUX command line prompt.
        41.

      41. At the LINUX command line prompt type exit to log out of the N2MASS / S2MASS computer.
        42.

      42. (North only) In the dome turn the air conditioning back on.

        The settings in the winter should be 50 degrees F.
        The settings in the summer should be 65 degrees F.

      43. Confirm that the Primary mirror covers and dome slit/flap are closed.
        44.

      44. In the dome, close the outside door and turn off the lights.
        45.

      45. (North only) Fill out the FLWO 2MASS observers log for the day crew.
        46.

      46. In the control room:

        • Turn off the space heater, if used.
        • Turn off the radio, if used.
        • Turn off the coffee maker, unplug, empty coffee pot, and throw away coffee grounds, if used.
        • Turn off all monitors and the oscilloscope.
        • Confirm that the camera electronics are turned off in the control room AND in the dome.
        • Confirm that the dome slit and flap are fully closed.
        • Confirm that the telescope drives are shut off (at least one RED crash button pushed in).
        • Tidy up the control room.
        • The control room door to the dome (NOT OUTSIDE) should be left open during the summer.
        • Turn off all remaining lights and exit the control room.

      47. (South only) If it is Thursday Morning, take the tapes on the shelf marked 'Tapes to Tucson' down to the cafeteria and put them in the 'Outgoing Mail' box for shipment back to the US. Make sure all outgoing tapes have a mailing label showing throught the case. Send mail to 'tape' listing the data tapes that are being shipped out.
        48.

      48. (North only) If it is the end of your shift, take the tapes down to the basecamp and place in Ginnee's inbox for mailing to IPAC. Make sure that the a mailing label is showing through the top case and tape all tapes together using packing tape.
        49.

    2MASS Operations Manual,  Eric Howard editor.

    Version 2.0 - March 19, 1998
    Version 2.1 - September 10, 1998
    Version 2.2 - September 30, 1998
    Version 2.3 - October 4, 1998
    Version 2.4 - January 8, 1999
    Version 2.5 - October 27, 1999

    66.