Help on PSF use for alignemnt during AO calibration

The example is written for the right side of the telescope (FALO#1), change right with left for the other side (FLAO#2).

Be sure to select the correct side of the telescope to not interfere with the work of other pepole.

General note on coordinates

PSF does not anything about rotator position, it deals only with telescope optics (M1+M2). The coordinates x and y refer to the telescope coordinate axis (on M1 for Zernike coeffs). Position of rotator it is not taken in account.


  1. from any workstation: PSFGUI right
  2. press "Secondary" button.
  3. type in the white fields of "Global Offsets" the current position of the Hexapod (see fiels in "Hexapod", "Platform Position"). When you type the numbers are red, press return to confirm the enter, the number will be transferred in the corresponding field below
  4. be sure that all the fields having the button "Remove Corrections" are all zero. Press the corresponding "Remove Correction" button in case some of them are not zero
  5. Press "Update" button in "Global Offsets"
  6. "Total collimation" and "Hexapod-Platform Position" should report the same values previously typed in Global Offset.

Change Coma-free Tip and Tilt wrt HP current position

  1. In the PSF main GUI press "Arbitrator" button to open the related GUI
  2. In the "Coma-free Pointing" be ABSOLUTELY sure to select M2 from the list selector "Ope"
  3. type the correction value in the fields "Tip" and "Tilt" of "Coma-free Pointing" panel. The values are on-sky arcseconds
  4. press "Send" button to apply the relative correction of Coma-free Tip-Tilt
  5. the contribution of the "Coma-free Pointing" entry in terms of hexapod positioning is shown in "XXX Offsets" and summed up in the "Total Collimation" panel
NOTE: the "Send" button integrates the correcting values written in the fields, ex. pressing twice the "Send" button the Hexapod will move twice the value reported in the fields

Change Tilt-free Coma wrt current HP position

  1. In the PSF main GUI press "Secondary" button if "Secondary Mirror Active Optics and collinatio Control" GUI is not yet open
  2. Press "Clear Coefficients" button in the "Zernike Coefficients" panel to be sure to clear the 22 elements of the Zernike vector to be used
  3. write 7 in field Number of "Zernike Coefficents" panel to select the ComaN. The value of ComaN will be set in the next step.
  4. write the ComaN value in the field "Value" in nm (rms?) WFE.
  5. write 8 in field "Number" to select ComaN
  6. write the ComaN value in the field "Value" in nm (rms=) WFE
  7. press "Send" button to apply the values of all the Zernike Coefficents including the previously set of ComaN e ComaN (for this reason clearing the vector at the beginning is important)
  8. the contribution of the "Zernike Coefficients" entry in terms of hexpaod positioning is shown in "XXX Offsets" and summed up in the "Total Collimation" panel
NOTE: the"Send" button integrates the valued reported in the fields

Change Focus wrt current HP position

The same as for Coma, but writing 4 in "Number" field of "Zernike Coefficients" panel

Change History

-- ArmandoRiccardi - 21 Sep 2010 First version
Topic revision: r2 - 21 Sep 2010, ArmandoRiccardi
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