NEWFIRM Manual

Here we describe the NEWFIRM observing GUI and discuss other information relevant for observing.

  • Open VNC viewers (NEWFIRM Obs and NEWFIRM IRAF)
  • Start NEWFIRM GUI in Obs VNC viewer
  • Press "Start of Night"
    • Opens environmental cover
  • Initialize system
    • Turn on detector power
    • Open filter tool
    • Initialize filters
    • Move filter position to "DARK" if the dark filter is not already in place
    • Set Proposal ID (PropID)
      • This will load the proposal PI and co-Is
      • No images can be taken unless the PropID is set to a valid PropID
    • Take a junk image to reset image counter/number
      • The image counter does not reset to 1 at the beginning of the night
      • Make sure dark filter is in place
      • Under Exposure Control:
        • Set Basename to "ajunk_"
        • Set Title to "Junk"
        • Set Exp. Time to "1.120"
        • Set Repeats to "0"
        • Set Coadds to "0"
        • Set Fowler to "1"
        • Set Sequence to "1"; This must be the last step.
        • Click "Expose"
        • The image counter will now be reset and calibration data will start with image number *0002*
  • Take flats
    • Ask telescope operator to point telescope to white spot
    • Open flats tool on NEWFIRM GUI
    • The default flat script will take flats for JHKs and 1644, 2124, and 2168
  • Take darks
    • Default script will take dark frames with exposure times corresponding to flat field exposure times
    • Add darks with appropriate exposure times, coadds, and fowlers as your expected science exposures
  • Start of night
    • Telescope pointing
      • Use J filter
      • Go to a recognizable field (e.g., a standard star or a bright star near zenith).
      • Identify the object on the detectors.  The pointing is generally good so the object may be located in the detector gap
      • Perform offsets until you can see the object on detector 3.  This usually will require offsets to the east and north.
      • Use NEWFIRM IRAF task zp.cl
        • You will be prompted for an image name
        • The task will load the image for detector 3 into the ds9 window and start the "imexam" IRAF task
        • You will be prompted to locate the object on the detector and press the "a" or "r" key to determine the pixel values of the centroid of the object.
        • The output will tell you the offset needed to place the object at the center of the detector gap.
      • Ask the telescope operators to perform the offset.
      • Ask telescope operators to perform the zero-point after the offset is complete.
    • Telescope focus
      • Use the J filter
      • Select telescope focus script "focus_wide"
      • Input the value for the center telescope focus value based on the ambient temperature. The telescope operators have a tool to predict best focus value depending on temperature.
      • Execute the focus sequence
      • When the focus sequence is complete, a list of the focus images is written to the file "/tmp/focuslist"
      • The IRAF nffocus task does not understand multi-extension FITS (MEF) files
        • Edit the "/tmp/focuslist" file to only use one detector by appending the desired detector to the lines in the focuslist file
        • Change <filename>_<####>.fits to <filename>_<####>.fits[D] where "D" is the detector number
      • Use IRAF nffocus tool to determine best focus
      • The table of focus offsets from the JX filter to other filters is available in table located at (focus offset table page)
  • Observing
    • Individual exposures
      • Set exposure time, coadds, and fowler
      • Select obstype
      • Choose basename
      • Title
      • Expose
    • Dithered exposures
      • All of above
      • Select grid pattern
      • Select number of grid steps in x and y
      • Select step size in x and y
      • Click OK
      • Click Start
    • Scripted exposures
      • Scripts can be text or JSON (examples of each)
      • Select Load
      • Click start
      • Sequences
        • Run multiple scripts

Updated on September 14, 2024, 8:00 am