NIRC2 Calibrations Check

NGS-AO (required for both, NGS and LGS calibrations)

  1. On the k2aoserver-new:3 VNC desktop, select from the background menu NGS-AO Control → Start NGS calibrations
  2. Launch NIRC2 GUIs. On the k2aoserver-new:2 VNC desktop, select from the background menu:
    • NIRC2 Menu → NIRC2 waikoko-new terminal
    • NIRC2 Menu → Start Quicklook
    • NIRC2 Menu → Start NIRC2 Status GUI
  3. Optional: On the waikoko-new terminal, type newdir if you would like to save the NIRC2 images in a new data directory. If the directory for user nirc2eng and current UTC date already exists, no new directory will be created.
  4. Keck II Calib → Calibration setup. If prompted:
    • Select NIRC2
    • Select NGS-AO
  5. SC GUI → SF (SFP) → obsfname → nirc2
  6. Keck II Calib → Light Source Control
    • 1% = ND2
    • If HEPA still on, Click for HEPA OFF
  7. Check that the AOACQ GUI is in simulator mode (Aoacq - vX.Y CLS Archon SIMULATION MODE). Otherwise, start the AOACQ GUI in simulator mode from the VNC pulldown menu:
    • K2 AO Tools → AO Acquisition (Simulation)
  8. In the Aoacq GUI:
    • mR → 11.5
    • AO Mode: NGS-AO
    • Ref: NIRC2
    • Seeing: 0.0
    • Background WFS: Auto
    • Run Setup bench
  9. Setup NIRC2 and take an open-loop image.
    1. If this is not a continuation of the AO calibrations, then you will need to load the latest image-sharpened DM voltage map. Otherwise, the open-loop PSF will look like a speckle cloud. This should not affect the closed-loop image quality, though.
    2. In a waikoko-new terminal:
      • Type user nirc2eng
      • Type ao_confirmation, which will do the following:
        set the object name to "ao_confirmation"
        set filt brgamma
        set camera narrow
        set pupil open
        set shutter open
        set grism clear
        set sampmode 2
        set subc 512
        set tint 0.5
        set coadd 20
        set wait4ao off
        Take an image using goi
  10. Check the open-loop image quality
    • Quicklook → Plot → Gaussian Fit.
    • Note the XFWHM,YFWHM. They should be less than 4.5 pix if the latest sharpened DM voltage map was loaded. An elongated PSF or a PSF with FWHM > 4.5 pix is considered poor. If the latest sharpened DM shape was not loaded, then the PSF will look like a speckle cloud and the open-loop image quality can be ignored.
  11. Aoacq GUI → Acquire star
  12. MAORI → AO Control
    • TT gain → 0.1
    • DM gain → 0.1
  13. In a NIRC2 control terminal type (goi) to take an image with the AO loops closed.
  14. Check the closed-loop image quality
    • Quicklook → Plot → Gaussian Fit.
    • Note the XFWHM,YFWHM. They should be less than 4.5 pix. An elongated PSF or a PSF with FWHM > 4.5 pix is considered poor.

Additional checkout for LGS-AO

  1. Open the AO loops if they are closed: MAORI → AO Control → LOOP → OPEN
  2. Light Source Control → 1% = ND2
  3. Start the LBWFS Img Acq GUI, if it has not been started yet
  4. In the Aoacq GUI:
    • mR → 13.0
    • AO Mode: NGS-ST
    • Ref: NIRC2
    • Seeing: 0.00
    • Update mR: OFF
    • Run Setup Bench
    • If prompted, select Sodium dichroic
    • Set FPS: m o1fps=20
    • Acquire star
    NOTE: The mR magnitude is set to a fainter value that it actually is to ensure high enough signal on the WFS.
  5. MAORI → AO Control
    • TT gain → 0.1
    • DM gain → 0.1
  6. Take a closed-loop image with NIRC2. In a NIRC2 control window type ao_confirmation, which will do the following:
    set the object name to "ao_confirmation"
    set filt brgamma
    set camera narrow
    set pupil open
    set shutter open
    set grism clear
    set sampmode 2
    set subc 512
    set tint 0.5
    set coadd 20
    set wait4ao off
    Takes an image using goi
    IMPORTANT NOTE: The same ao_confirmation script should be used for NGS-AO and LGS-AO image quality checks after the K2AO light source was replaced with the fainter K1AO source in June 2025.
  7. Check the closed-loop image quality:
    • Quicklook → Plot → Gaussian Fit.
    • Note the XFWHM,YFWHM. They should be less than 4.5 pix. An elongated PSF or a PSF with FWHM > 4.5 pix is considered poor.
  8. On the the LBWFS Imag Acq GUI:
    • Change the integ(s) to 2.0 seconds
    • Click Loop
  9. Manual LBWFS focus control. Read the focus value (mm) of the black curve (left Y axis) on the Low-Bandwidth Manager GUI and subtract the value from the position of the FCS stage. This can be done using one of the following two methods:
    • Option 1: SC GUI → WF (FCS) → obwf , update value in the green box and hit S
    • Option 2: On a k2aoserver-new terminal type:
      • s obwf to show the current FCS focus value
      • m obwf=new_value to move the FCS focus to the new position
    The black line on the Low-Bandwidth Manager GUI should be reporting near zero after the FCS move is sent. The focus is fine if the values are <0.15mm.
  10. Close COG control on the Low-Bandwidth Manager GUI after correcting the focus and make sure to let it run for at least 10 iterations. Verify that the fast WFS COG updates on the Low-Bandwidth Manager GUI. Evaluate performance:
    • Take additional NIRC2 images. The image quality should still be acceptable after 10 iterations of the LWBFS COG control loop.
    • The reported RMS WFE (red plot in the Low-Bandwidth Manager GUI) should be ≤ 250nm after it converges. The value should improve with the COG control loop closed. If it fails to converge either the configuration is wrong, e.g. insuficient light in the LBWFS, or the calibration is wrong.
  11. Once you are done:
    • Hit HALT on the LBWFS Imag Acq GUI
    • Uncheck the cog ctrl box on the Low-Bandwidth Manager GUI
  12. Open AO loops: MAORI → AO Control → LOOP → OPEN

Put everything in safe mode

  • In a NIRC2 control window type shutter close
  • Keck II calib → Shutdown AO Bench
    • If AO loops are still closed, select Open loops.
    • Keep WFC in NORMAL if the bench will be used within the next hour. Otherwise, put WFC in STANDBY.
    • Put STRAP in STANDBY? Select No if the bench will be used within the next hour. Otherwise, select Yes.
    • Acknowledge popup message indicating OCAM2k will be warmed up by pressing OK.
    • Select Turn HEPA ON if none of the conditions specified in the popup message are fulfilled.
    • Turn AO light source off (select Yes in the popup message) if AO bench work is completed and there is no intention to resume work any time soon.
    • Answer Yes to send the SFP to the Telescope position if the AO bench needs to be prepared for night observing.
  • If you need to "manually" move the SFP to the telescope position, in the SC GUI
    • SF (SFP) → obsfname → prehome (wait until INPOS)
    • SF (SFP) → obsfname → home (wait until INPOS)
    • SF (SFP) → obsfname → telescope
  • In the case of NGS-AO calibrations, select on the background menu NGS-AO Control → Stop most NGS-AO Software
  • In the case of LGS-AO calibrations, select on the background menu LGS-AO Control → Stop most LGS-AO Software
Last modified: 07/05/2025 10:28
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