New in 2016B: 

For the first collimation of the night, or after clearing active optics, please use dohybrid instead of dofpia, /first.  dohybrid combines the focus and collimation routine, WRS, under development in Rome, with dofpia. WRS is much better at removing the large amounts of coma that are sometimes present at the beginning of the night and therefore can bring the pupils into the ‘keyhole’ where dofpia can work on them. dohybrid should eliminate the need for manual focus corrections, so this ‘by-eye cartoon’ may be history!

How to Observe with LBC

1) LBC Instrument Start-Up

2) Other Software Start-up

3) Executing an LBC Script

4) LBC Calibration Frames

5) Collimating and Co-Pointing LBC

6) LBC End of Night

7) LBC Basic Troubleshooting

 

LBC Instrument Start-Up:

The following should be completed beforehand by the ISA, TO, or Instrument Tech on duty. However, it is important to familiarize yourself with the directions in case you need to restart software or change instruments in the middle of the night:

  • Log into LBTO workstation (obs2 recommended) using your partner account (INAF, LBTB, OSURC, AZ)
  • Start a Firefox browser
  • Type “lbccontrol” in the URL box and hit return. In the Welcome to the LBC Control page, click “LBC Control Interface”. Then click “Enter” on the next page that appears; this will open the LBC User Interface (UI) in another window
  • Go to the Power Control page. Check if HouseKeeping is on by confirming that status reads “READY” and the “Turn ON House Keeping” button should be greyed out. If HouseKeeping reads “ENABLE” or has an error message, please tell your TO/OSA immediately.
  • If it is cold (< 0C) outside, first click “Warm Up” and leave that for 15-30 minutes. Turn on “Other Systems”. Wait for status of all systems in Other System in both channels to read “Ready”. This may take 2-5 minutes.
  • Confirm with OSA that LBC is authorized. Then click Connect to establish telescope-instrument communications. For binocular operation both Right and Left should be checked.
  • Open an xterm and type “RB_Science” (or “Blue_Science” or “Red_Science”, if only LBC Blue or LBC Red is to be used). RB_Science is a “quicklook” tool that will automatically query the /newdata directory and display the latest LBC images.
  • Once the LBC software is up and running, take a test bias.
  • Test scripts are located in /home/LBTO/Calib_OBs/BIASDARK. Use OneBias_Bino.ob if dome lights are on, 10Bias_Bino.ob if they are off.
  • Follow the directions in “Executing an LBC Script”
  • Biases should be approximately 500 counts
  • In an xterm, cd /newdata and confirm that the images are in the archive

 

Other Software Start-Up:

These steps should be completed by the observer to prepare for observing:

  • Open an xterm and type “IIFGUI &” to bring up the IIF GUI display. This GUI will allow you to keep track of the position of the telescope and will help confirm when commands to the mount & mirrors are completed.
  • Open another xterm and type “idl” to start an IDL session.
  • Start IRAF
  • >> cd into the iraf directory. It is most likely a subdirectory in your user’s home directory (i.e. /home/lbto/iraf)
  • open an xgterm
  • in the new xgterm > cl to start IRAF
  • > epar LBTtools and set the observer, camera, archive (/newdata) and the correct UT date. Usually camera = LBC for binocular activities. When in doubt, use “?”  Exit with a :go to save your changes and load the package.
  • Create a directory in /scratch with the UT date (ie 20130330)
  • In the IRAF session, >> cd to the newly created directory in /scratch and run prepdir. This will “prepare” the directory by creating subdirectories used to keep logs and other files created by LBTtools  organized

 

Executing an LBC script

  • On the OB Execution UI, click (1) “Browse” to locate the OB.
  • Upload the OB by (2) clicking the downward pointing arrow. The OB name and basic information will appear to the right.
  • Play the OB using the (3) right-pointing arrow
  • Confirm that the data are displayed correctly in RB_Science.

 

LBC Calibration Frames

Biases:

  • Ask the TO to turn off the dome lights.
  • Confirm the telescope is stationary.
  • Load and play bias scripts. Several are located in /home/lbto/Calib_OBs/BIASDARK.
  • We recommend 10-25 biases every night the instrument is in use.
  • Biases should be ~500 counts

Flats:

  • Flats for LBC are always taken open dome in morning or evening twilight
  • The perl script mkskyflat will create a binocular OB to take a series of 5 dithered exposures about a specific or “standard” position and a binocular “FlatTest” OB. The script takes a series of arguments; type mkskyflat with no arguments to see the syntax.
  • The “standard” position for twilight flats is at an hour angle, HA ~ -00:30, and declination = 27 degrees, close to the zenith. However, if this coincides with the Galactic plane, or you have a preferred position, you may create the OB with these coordinates. A table of coordinates of 23 blank sky fields for sky flats is available from the ING web site.
  • After creating the OBs, load and run the FlatTest OB. This will read-out a small portion of the detector to check count levels. Once you are satisfied with the counts, load and run the 5-dither flat OB.
    • Count levels will depend strongly on the photometric errors necessary to accomplish your science goals.
    • We recommend a total of at least 100,000 electrons (50,000 counts) to provide <1% photometric error
    • To rectify the affects of cosmic rays, etc. we suggest 5-8 frames of 20,000-30,000 counts each.
    • Flats should move from bluest to reddest after sunset athough special consideration should be paid to narrowband filters (i.e. U-spec). Note: U-Bessel and U-spec should be started immediately after the sun sets.  The Y band data may need to be taken before i and z bands because of dropping CCD quantum efficiency at longer wavelengths.  The order generally reverses at sunrise.
  • If adjustments to the exposure time need to be made on-the-fly to correct the count levels, use the “scale exposure time” box on the left upper corner of the OB Execution UI. To use this feature, the OB must already be uploaded, but should not be playing.

Collimating and Co-Pointing LBC

WHEN THE PI *HAS* PROVIDED A POINTING OB:

  • Following the directions outlined in “Executing an LBC Script” load and run yourCoPoint.ob
  • STOP the OB as soon as the telescope presets. You DO NOT want LBC to take any data yet
  • Wait for the telescope to be in position. In the idl window, run dohybrid if this is the first collimation of the night, or the first after clearing active optics or dofpia, /X2 (X2 doubles the exposure time to 32 seconds, and averages over seeing variations, but should not be used for fields near the zenith, i.e. at elevation > 85 deg). If, for some reason, you have chosen to ONLY use LBCR or LBCB, add the flag /RedOnly or /BlueOnly.
  • Once dofpia is completed and converged, run yourCoPoint.ob, allowing it to complete and take the in-focus images
  • In your IRAF session load Observe
  • >> unlearn lbcrangebal
  • Epar lbcrangebal and enter the timestamp number from the filenames for the red and blue images taken by the yourCoPoint.ob script
  • run lbcrangebal on these images; follow the direction in IRAF; This corrects pointing (IE and CA) and co-pointing (SX, DX M1s). (If using only LBC Blue or LBC Red, run, instead, LBTtools.LBC.ptautoadjust to adjust the pointing only)
  • You are ready to observe!

 

WHEN THE PI HAS NOT PROVIDED A POINTING OB:

  1. Pre-made PointingOBs from pointing star list:
    • Have the OSA choose a pointing star from their list that is close to the target
    • Browse for and upload the corresponding OB from /home/lbto/Calib_OBs/RB_VV_PointingOBs/. OB names are of the form StarName.ob
    • Play the OB to slew. Stop the OB. Wait for the telescope to be in position.
    • In the idl window, run  dohybrid or dofpia, /X2 (see note above for an explanation when to use dohybrid and when to use dofpia).
    • Once dofpia is completed and converged, run  the RB_VV_Pointing OB for your target, allowing it to complete and take the in-focus images
    • In your IRAF session load Observe
    • Epar lbcrangebal and enter the name of the red and blue image taken by the yourCoPoint.ob script
    • run lbcrangebal on these images; follow the direction in IRAF; This corrects pointing (IE and CA) and co-pointing (SX, DX M1s). (If using only LBC Blue or LBC Red, run, instead, LBTtools.LBC.ptautoadjust to adjust the pointing only)
    • You are ready to observe!
  2. Create your own Co-Pointing script and finder chart via an OBS-N computer with “FindCPS”:
    • On an obs-N machine, you may run the program from any directory.
    • In the terminal window, type “findcps hr min sec +deg min sec” – where the hr min, etc are the RA and Dec of the science field (i.e. findcps 00 00 00 11 23 34).
    • A DS9 window should pop up with a green stars circled. These stars are of the right brightness for a 1 sec exposure.
    • Left-click any star with your mouse (select a star that is easily recognizeable).
    • In the terminal, paste the coordinates (center button/wheel on mouse) and hit return.
    • A new DS9 window will pop up showing the approximate Chip 2 field and the star highlighted.  The green box shows the field that will be seen by DOFPIA for collimation.
    • NOTE: The current version shows the old DOFPIA field, we have changed DOFPIA to collimate on the same size field BELOW the co-pointing star.  This will be updated soon.  Keep this in mind when selecting an area with enough stars that DOFPIA can run and collimate well.
    • Hit RETURN.  The DS9 windows will vanish.  Type ‘ls’ in the terminal and you should see two new files.  A *.ob and *.jpg with the RA and Dec of the field you originally passed to findcps.  Copy these two files to your working directory.
    • Load and Play the new OB you made withe findcps to slew. Stop the OB. Wait for the telescope to be in position.
    • In the idl window, run  dofpia, /X2, /first (the X2 doubles the exposure time to 32 seconds; first should ONLY be used at the beginning of the night or after the AO has been cleared)
    • Once dofpia is completed and converged, run  the RB_VV_Pointing OB for your target, allowing it to complete and take the in-focus images
    • In your IRAF session load Observe
    • Epar lbcrangebal and enter the name of the red and blue image taken by the yourCoPoint.ob script.
    • Use the *.jpg file as a finder chart to selecting the correct star.
    • run lbcrangebal on these images; follow the direction in IRAF; This corrects pointing (IE and CA) and co-pointing (SX, DX M1s). (If using only LBC Blue or LBC Red, run, instead, LBTtools.LBC.ptautoadjust to adjust the pointing only)
    • You are ready to observe!

     

LBC End of Night

  • In the Power Control UI, disconnect LBC from the telescope using the Disconnect LBT button
  • In the Power Control UI turn off the instrument with the Turn Off button
  • In IRAF type LBC to load that package and then run allseeing

 

LBC Basic Troubleshooting

These common issues range from the very simple ones, which can be resolved with one step, to more complicated problems that might require multiple layers of troubleshooting. Still, everything listed under this Basic Troubleshooting section can be completed by either LBTO Support Staff OR visiting astronomers and thus the directions are listed here. If these solutions do not work or the problem is more serious, please inform the OSA or ISA on duty.

ISA and OSA can link to the password protected LBC Advanced Troubleshooting section.

 

I) LBC software hangs

II) RB_Science crashes

III) IRAF crashes

IV) IRAF cannot write logs

 

I) The LBC software hangs or is unresponsive:

  • Stop the OB with the STOP button on the OB execution UI
  • If that doesn’t work: gracefully stop and restart LBC in the power control UI.
  • If that doesn’t work, ask the OSA/ISA to stop and restart the software via the lbc cmu. Details for OSA/ISA are found here.

II) RB_Science hangs:

  • Close RB_Science using a CTRL-C in the terminal window where the task was started.
  • If it continues to relaunch >> pkill RB_Science
  • If this does not work, find the process ID# (PID, second value listed) by typing in the command line on a terminal window

>> ps -ef | grep RB_Science
inaf     16041 12315  0 03:38 pts/51   00:00:17 /usr/bin/python/home/lbcobs/supportscripts/ObserverSupport/RB_Science.py
inaf     16043 16041  4 03:38 pts/51   00:22:46 /lbt/astronomy/stow/ds9-6.2/libexec/ds9 -geometry 940×1200 -title RB_Science
lbto     25546 25526  0 12:05 pts/44   00:00:00 grep RB_Science

  • Once you have the PID number, on the command line type:

>> kill -9 16041

  • You will have to keep killing jobs until RB_Science stops re-launching

III) IRAF task or program problems

  •  >> unlearn task. Then reenter your specific parameters (epar) and try again.
  • If that does not help and you must leave iraf, do a >> logout out the iraf xgterm
  • MAKE SURE YOU ARE IN THE RIGHT DIRECTORY (~/iraf) and then run cl again. When in doubt >> cd  and then >> cd iraf
  • Don’t forget to move back into your working directory: >> cd /scratch/UTDATE
  • Remember to load all the correct packages before continuing (LBTtools, Observe)

IV) IRAF imexam, lbcrangebal cannot write a log

  • You may be working in /newdata which is read only.
  • The LOGs directory may not exist.  Follow the directions in the Start IRAF section and run prepdir.