Fan Mountain 31-inch Telescope
& FanCam Manual


06 June 2006
The IR Group
Department of Astronomy
University of Virginia


1 Introduction

The 31-inch telescope at Fan Mountain Observatory is an equatorial-mount classical cassegrain reflector. It has been realuminized with enhanced throughput in the near infra-red in 2004. FanCam, a near-infrared imager-polarizer-spectrograph was commissioned on this telescope in December 2004.

FanCam is currently the only instrument in commission at the 31-inch telescope. The instrument usually remains on the telescope through most the year except when it is taken down for the two Fan-Mountain Public Nights and for occasional servicing.

2 Rules of Operation

The Fan Mountain Observatory is intended for use by University of Virginia astronomers and students. The Observatory is an important resource for numerous research projects and strict rules are in place to ensure that the Observatory operates soomthly and without disruption. It is important that prospective observers acquiant themselves with all the necessary Dos-and-Donts of the Observatory in general as well as the individual telescope they intend to use.

At present, there is no online reservation option for the 31-inch telescope because the telescope and FanCam are still in the midst of upgrades. Prior notification and atleast acqueiscence must be obtained before undertaking any bout of observing with the 31-inch telescope. Due to various security reasons, the passwords for the computers are changed regularly and passwords will be provided only in person.

The Telescope and FanCam may NOT be operated without explicit training and familiarization by authorized 31" operators in the department. The telescope is not grounded properly, and care needs to be taken while operating FanCam. Care must also be taken to protect against static during the winter and thunderstorms during the summer.

It is imperative that the start-up and shut-down procedures be followed religiously. This will ensure that the telescope and FanCam are not placed at unneccesary risk either during observing or afterwards. It will also ensure that the subsequent observers will find everything in order and will not have to deal with problems arising from a disorderly start-up.

3 Telescope and FanCam Specifications

3.1 Telescope

3.2 FanCam

4 Finding Your Way Around

4.1 Dome Room

4.2 Telescope

4.3 FanCam

4.4 Control Room

4.5 Computers

5 Observing Procedures

5.1 German-Flipping the Telescope

The telescope has a German Equatorial Mount which means that the telescope pier obstructs the telescope and it can not freely take any position on the sky. The telescope can observe only about half the sky from any one side of the pier. The telescope can point at a rising target from the west side of the pier until approximately 30 minutes past transit. Similarly, the telescope can point from the east side of the pier at targets only from within 30 minutes before their transit upto when they set. To observe a target in the part of the sky inaccessible from either side of the pier, the telescope must be moved to the other side of the pier.

You will need to initialize the telescope again after going through this procedure :

  1. Make sure the telescope RA drive is clamped, and unclamp the DEC drive.
  2. Point the the telescope to the north pole(along the axis of the RA bearing on the telescope pier)
  3. Clamp the DEC drive and unclamp the RA drive.
  4. Move the telescope over the pier to the east side until the RA arm is horizontal.
  5. Clamp the RA drive.
  6. Remember to change the telescope configuration in PC-TCS using the procedure described in Sec 5.3 on Page [*].
  7. Remember to initialize the telescope again before continuing observing. The procedure is given in Sec 5.2 on Page [*].

5.2 Initializing the Telescope

Since the telescope has an equatorial mount, one of its axes is "permenantly" aligned with the axis of earth's rotation. This means that the telescope needs only one star for initialization. This procedure will be needed every time you "german-flip" the telescope as well.
  1. Point the telescope at a (not too bright)star that you can easily identify on the part of the sky you wish to observe.
  2. Use the Telrad on the telescope, and center the star in the "bull's eye" from the Telrad.
  3. Return to the Control Room.
  4. The star should be visible on the Finderscope screen. Move it to the center of the Field-of-View window for FanCam using the controls on the Telescope Control Panel.
  5. Enter the coordinates for the star into the 'Next' field on the PC-TCS using either of the procedures described in Sec 5.6 on Page [*].
  6. On PC-TCS, enter the menu 'Declare' and select the item 'Init Next'. Press 'Enter' and confirm the change with the key 'Y'.
  7. Move the star out of the Field-of-View of FanCam.

5.3 PC-TCS Telescope Configuration Change

  1. Go to the exit menu on the PC-TCS.
  2. Select 'Manual Stow', press 'Return', press 'Escape', press 'Return'.
  3. At the prompt, type 'pfcom' and press 'Return'.
  4. In the program menu of pfcom, go to menu item 'Telescope'.
  5. Go down to item 'Tube East', press 'Return' and then move to the menu item 'Exit' and exit.
  6. Type 'tcscom' at the prompt and press 'Return'. The tcscom screen should now reflect the modified option you chose on tube position.

5.4 Using Xephem

Observers should familiarize themselves with Xephem atleast before attempting solo observations. A very clear and thorough manual for Xephem is available on the web at

  1. Start Xephem using the icon located on the desktop of "thirtyone".
  2. When started, the main window shows the location of the observatory and time and other settings.
  3. The menu item 'View:Sky View' will open the "Sky View" window.
  4. The various options on the periphery of the window allow you to view the sky in different co-ordinates.
  5. The view you see will include stars and other objects that have been loaded into Xephem using database files. See Sec. 5.5 on Page [*] for further information on how to load objects into Xephem.
  6. You can search for loaded targets, make your own target lists and look at DSS images of any part of the sky using Xephem.
  7. We also use Xephem to input target coordinates into PC-TCS for observing. See Sec.5.6 on Page [*]

5.5 Loading Target-lists into Xephem

  1. Create a file with an extension .edb.
  2. Enter the target name, object type, coordinate, magnitude and epoch information into the file in this format:
    More information on the target database file formats can be found at
  3. Move the file to the directory /home/observer/.xephem/.
  4. Use the menu option 'Data:Files' on the Xephem main window. This will open a 'Database Files' window.
  5. The Menu item 'Files' in the 'Database Files' window should now include all the available target lists. Use this menu to load your target list.
  6. The 'Sky View' window and subsequent searchs in the 'Loaded Objects Index' window will reflect this addition as well.

5.6 Entering Target Coordinates into PC-TCS

There are three different options on how to enter target coordinates into PC-TCS. Depending on your convenience, choose one of the methods below. If you have more than one target, or have to observe the target more than once, it is recommended that you use target-lists and the method 2 or 3 described here. The procedure to create and load target-lists into Xephem is described in Sec 5.5 on Page [*].
  1. Manual Entry Using the PC-TCS Screen :
    1. Enter the 'Position' menu in PC-TCS.
    2. Move to the option 'Next' and press 'Enter'
    3. In the next few screens, enter the 'Epoch', 'RA and 'DEC information. There is no need to worry about the options on proper motions unless the Epoch is very old.
    4. Confirm the inputs with a keypress 'Y' where prompted.
  2. Using the XEPHEM 'Sky View' window: The target needs to be loaded into Xephem beforehand.
    1. Right-click on the target on the "Sky View" window of Xephem and select the option "Telescope Go To".
    2. Repeat this a few times to ensure the coordinates are indeed transferred to the PC-TCS Screen for the coordinates option 'Next'.
  3. Using XEPHEM 'Loaded Objects Index' window: The target needs to be loaded into Xephem beforehand.
    1. In the space provided for "search" in the Xephem Loaded Objects window, type in the first few characters of the target's name as commonly known(if the target is being acquired from public database files) or the name given to the target by you in the target list you uploaded.
    2. Click on the target from the list of target options shown on the right. The target information should be shown on the left.
    3. After virifying the target, click on the 'tel GoTo' button on the bottom a few times. This should enter the co-ordinates into the field 'Next' on the PC-TCS Screen.
Though PC-TCS is designed to be able to control the telescope, it is not in use at this facility. We still enter the Coordinates into PC-TCS to make the process of moving to a new target easier. See Sec. 5.7 on Page [*] for further information.

5.7 Moving to a Target

5.8 Changing Filters

5.9 Using Voodoo

5.10 Using IRAF

5.11 Focusing the Telescope

5.12 Taking Flats and Darks

5.13 Observing in the Polarimetric Mode

5.14 Observing in the Spectroscopic Mode

6 Startup Procedure

This procedure MUST be followed every time to insure that the telescope and all electronics are in the 'default' setting, so that problems and troubleshooting can be minimized.
  1. Enter the Control Room.
  2. Turn on the three computer screens on the computer table.
  3. Login at the X-console on FanCam.astro and Thirtyone.astro.
  4. On the telescope control panel on the table on the right, check that the telescope tracking is turned off(the far left toggle switch).
  5. Go to the Dome Room.
  6. Turn the heat lamps off.
  7. Turn the white lights on.
  8. Plug in the RA & Dec cables on the panel above the light controls.
  9. Plug in the 4-prong cable hanging from the Dome Control Panel into the same panel as above.
  10. Unplug the Mirror Fans using the connection provided on the power-cord. Do NOT unplug the AC-to-DC converter from the socket on the pier.
  11. Turn the telescope power on using the toggle switch in the telescope mount.
  12. Take the blue cover off the telescope pier and store it on the pneumatic lift by the wall.
  13. The telescope should be parked pointing at the zenith on the west side of the pier. The cover over the telescope truss will have made the telescope unbalanced. Make sure the telescope is locked and is holding itself up, and pull the movable stairs from underneath the telescope frame. Park the stairs over by the wall.
  14. The telescope will be unbalanced, and is parked in an unstable orientation. Hold on to one of the large handle bars on the telescope, unclamp the DEC drive, and slowly point the telescope to the north horizon and clamp the DEC drive. During this process, make sure that the additional torque does not overcome the RA drive clamp and push the telescope down. Also make sure that the telescope is never pointed below the horizontal.
  15. Go to the front of the telescope and carefully pull the telescope cover off the truss. Store the cover under the pneumatic lift.
  16. Pull the stairs up next to the telescope truss and climb up. Reach in and open the latches holding the primary mirror covers down. Pull open the doors all the way and latch them using the hooks on the truss.
  17. Reach into the secondary mirror baffle and remove the secondary cover. To remove the cover, you will have to rotate the cover until it clears three tabs sticking in from the baffle. Care should be taken to avoid scratching the secondary. Place the cover on the table on the east side of the pier.
  18. Take the covers off the finderscope and the IR-sky camera. Make sure not to rotate or change focus of the c-mount lense on the IR-sky camera while taking the cover off.
  19. Connect the respective RCA video cables to the video outputs of the finderscope and the IR-sky camera.
  20. Connect the power-cords to the finderscope and the IR-sky camera.
  21. Reach in, carefully lift up and take the window-cap off FanCam and place it on the table. Point the telescope higher in the sky if needed to reach the window-cap on the dewar.
  22. Pull the stairs by the side of the electronics on the telescope and climb up. match up and plug in the two cables hanging by the FanCam dewar into the sockets on the two boxes at the back of the dewar.
  23. There should be two black power-cords hanging by the white power-strip on the electronics panel on the telescope. Plug them into the power-strip.
  24. The two power-cords are connected at the top of the power supply box and the leach box. Turn-on the switches next to the power-cords on either box.
  25. Connect the power-cord hanging from the slit motor to the socket on the power-cord hanging from a wall-connection on the south-side of the room. If needed, rotate the dome to bring the connectors within reach of each other.
  26. Push and hold the toggle switch on the connection to the left until the dome has opened completely and the slit motor stops on its own.
  27. Disconnect the slit motor power connection.
  28. If you want to start the observations on the opposite side of the pier to where the telescope is currently positioned, "german-flip" the telescope using the procedure described in Sec 5.1 on Page [*].
  29. Unclamp the DEC drive and point the telescope as close to vertical as possible by unaided eye. Clamp the DEC drive.
  30. Turn off the lights in the Dome Room.
  31. Return to the Control Room.
  32. Turn on the PC-TCS monitor behind the Telescope Control Panel.
  33. Start the PC-TCS computer.
  34. The PC-TCS computer should start the TCS program on boot. Check the TCS telescope orientation on the top right of the TCS screen.("tube east" or "tube west")
  35. If the telescope tube(ie, the telescope) is not on the same side of the pier as assumed by the PC-TCS, change the PC-TCS configuration as described in Sec 5.3 on Page [*].
  36. On the "Thirtyone" screen, start the web browser using the icon on the bottom of the screen.
  37. Use the bookmark on the browser toolbar titled "Fanweather". This webpage updates every ten minutes and contains all the neccesary information on the health of FanCam as well as weather and sky conditions.
  38. Gaim should already be running. If not, open a terminal and type 'gaim &' and press 'Return'. Gaim should automatically login using the login created for the observers' convenience. This is the preferred means of contacting people from the IR Group for exigent as well as non-exigent assistance.
  39. Use the icon on the screen to start Xephem.
  40. On the "FanCam" screen, start ds9 using the icon on the screen.
  41. Open a terminal and create a directory with the name reflecting the date of observations. The directory for observation in the evening or night of 07 March 2006 or the early morning of 08 March 2006 would be /home/observer/fan/20060308/.
  42. Start the Voodoo software using its icon on the screen.
  43. The "data directory" option on the voodoo window is set by default to /home/observer/fan/. Change it to the directory you have created above.
  44. Turn on the CRT screen on the table on the right by pulling on the knob at th top. This is the IR-sky camera screen and you should be able to see the Telescope structure in the foreground.
  45. On the middle screen on the table on the left(the second screen for "Thirtyone"), press the button labeled PIP. This should create a small window on top of the computer desktop. Switch through the options until the text says "PIP / Video". The video is from the finderscope. The small square window pasted on the video screen is the approximate field of FanCam.
  46. On the telescope control panel on the right, turn on the tracking using the toggle switch on the left. The LED should light up. Press the 'Set' button on the top of the panel. The telescope is now tracking.
  47. Initialize the Telescope using the procedure described in Sec 5.2 on Page [*].
  48. If needed, focus the telescope using the procedure described in Sec 5.11 on Page [*].

7 Shutdown Procedure

This procedure MUST be followed every time to insure that the telescope and all electronics are in the 'default' setting, so that problems and troubleshooting can be minimized.
  1. Turn off the telescope tracking using the toggle switch on the left end of the Telescope Control Panel. Remember to press the 'Set' key at the top to activate the change.
  2. Close 'Voodoo', 'IRAF' and 'ds9' on "Fancam".
  3. Close 'Gaim' and the web browser on "Thirtyone".
  4. Logout on both the computers.
  5. Turn off the PC-TCS computer. Use the power button on the CPU.
  6. Turn off the IR-sky monitor.
  7. In the Dome Room, turn on the white lights.
  8. Move the Dome Slit to parking position (south) using the controls on the wall.
  9. Connect the power to the slit motor.
  10. Close the slit and disconnect the power connection.
  11. If the telescope is on the east side of the pier, move the telescope to the west side using the procedure described in Sec 5.1 on Page [*].
  12. Park the telescope horizontally, pointing to the northern horizon and clamp it.
  13. Position the stairs by the telescope, climb up and turn off the power on the two electronics boxes.
  14. Disconnect the the two cables on the FanCam dewar.
  15. Diconnect the power-connection and the RCA video connection for the finderscope.
  16. Diconnect the power-connection and the RCA video connection for the IR-sky camera.
  17. Carefully put the FanCam window-cap back on.
  18. Also replace the covers on the IR-sky camera and the finderscope.
  19. Position the stairs by the telescope truss and climp up.
  20. Close the Primary mirror doors and put the secondary cover back in.
  21. Pull the stairs back a little. Cover the telescope front with the gray cover. Be mindful that if excessive force is used, the telescope clamps will come slip and drive the telescope into the pier.
  22. The cover should hang over the front of the telescope so that the center of the cover is approximately behind the secondary mirror.
  23. Pull the stairs back to the wall.
  24. Hold on to the Telescope handle bar and unclamp the DEC drive.
  25. Carefully hoist the telescope up into the vertical position and clamp the DEC drive. Be careful not to let the RA clamp slip.
  26. Place the stairs under the shoulder of the telescope.
  27. Ensure that the telescope is as close to vertical as possible with the stairs under it shoulder, but is not leaning on the stairs.
  28. Check the RA and DEC drives to verify that they hold up.
  29. Turn the telescope power off on the pier.
  30. Reconnect the mirror fans on the telescope.
  31. Disconnect the RA, DEC and Dome Control cables on the wall.
  32. Turn on the heat lamps.
  33. Turn off the white lights.
  34. Close the Dome Room door behind you.
  35. When you leave, make sure the two internal doors are closed and the two external doors are locked.

8 Data Storage, Archiving and Reduction

The computers at Fan are primarily for data acquistion alone. The data will have a finite lifetime there. The FITS files should be compressed using 'gzip' at the end of the night so they take up less space. Observers should plan on writing a CD on "thirtyone" at the end of the night. The compressed files would allow for nearly 500 frames, or approximately a whole night's worth of data to be written on a single CD. The cd-writer program 'cdrecord' and the X-interface for it 'xcdroast' are available on "Thirtyone".

There is no specific data reduction pipeline for reducing FanCam data. The observer should determine their own reduction procedures and observing methodology based on the targets and intended science.

9 Troubleshooting

10 Contacts and Emergency Procedures

For further information on capabilities and availability, contact Mike Skrutskie (mfs4n, 924-4328). Given adequate notice, someone from the IR group will assist you in becoming self-reliant in observing with the 31-inch Telescope.

If in need of help while at the telescope, contact whoever from the IR Group is available on Gaim. The standard login on Gaim on "thirtyone" should put you in touch with whoever is online from the IR Group at that time. Emergency contact information is available on the notice-board in the Control Room.

In an emergency of any nature, the procedure below MUST be implemented before trying anything else:

  1. Turn off power to FanCam, and disconnect the cables from the dewar.
  2. In case of precipitation, move the telescope slit to parking position(south) and close the slit. Remember to disconnect the power-connection.
  3. Turn the tracking off on the telescope control panel in the Control Room. Remember to press 'set' at the top of the panel to activate the change.
  4. Park the telescope horizontally(facing north) on whichever side of the pier the telescope happens to be.

11 Startup Check-list

This list is only a reminder, for use by those observers who are very comfortable with the system. The startup procedure that MUST be followed is explicitly given in Sec 6 on Page [*].

  1. Login on the two computers in the control room.
  2. Turn on the white lights in the Dome.
  3. Turn Heat lamps off.
  4. Connect the RA, Dec and Dome control cables on the wall.
  5. Disconnect mirror fans.
  6. Remove the coverings on the telescope and the pier.
  7. Remove the Primary and secondary covers.
  8. Remove the covers for the IR-sky camera, finderscope and FanCam.
  9. Connect the video and power cables for the IR-sky camera and the finderscope.
  10. If needed, turn on the Telrad.
  11. Connect the FanCam cables. Plug in the power-cords and turn on the power on two boxes.
  12. Open the Slit. Disconnect the power-connection.
  13. German-flip if needed. Point to zenith.
  14. Turn off the white lights.
  15. Turn on PC-TCS.
  16. Start Xephem and Weather pages. Check for GAIM.
  17. Start Voodoo, ds9 and IRAF.
  18. Create a data directory and point Voodoo to it.
  19. Turn on the IR-sky monitor and the inset finderscope window.
  20. Start tracking.
  21. Initialize the telescope.
  22. If needed, focus the telescope.

12 Shutdown Check-list

This list is only a reminder, for use by those observers who are very comfortable with the system. The shutdown procedure that MUST be followed is explicitly given in Sec 7 on Page [*].

  1. Turn off the telescope-tracking.
  2. Shut down all applications and logout of the two computers.
  3. Turn off the PC-TCS computer.
  4. Turn off the IR-sky Monitor.
  5. Close the Dome Slit.
  6. Park the telescope horizontally, pointing North on the west side of the pier.
  7. Turn off and disconnect FanCam.
  8. Turn off and disconnect the IR-sky camera, finderscope.
  9. Turn off the Telrad.
  10. Cover the FanCam window, IR-sky camera and the Finderscope.
  11. Cover the primary and the secondary mirrors.
  12. Cover the front of the telescope.
  13. Hoist up the telescope into the vertical position and clamp it.
  14. Park the stairs under the telescope shoulder.
  15. Reconnect the mirror fans.
  16. Turn off the telescope power.
  17. Disconnect the RA, Dec and Dome control cables on the wall.
  18. Turn on the heat lamps.
  19. Turn off the white lights.
  20. Close the Dome door behind you.
  21. When you leave, check that the two internal doors are closed, and the two external doors are locked.

About this document ...

This document was generated using the LaTeX2HTML translator Version 2002-2-1 (1.70)

Copyright © 1993, 1994, 1995, 1996, Nikos Drakos, Computer Based Learning Unit, University of Leeds.
Copyright © 1997, 1998, 1999, Ross Moore, Mathematics Department, Macquarie University, Sydney.

The command line arguments were:
latex2html -split 0 -image_type gif -nonavigation -show_section_numbers Fan31man

The translation was initiated by Srikrishna Kanneganti on 2006-06-13

Srikrishna Kanneganti 2006-06-13