Collimation and Pointing:

  1. Iterate on collimation and pointing:
    1. Obtain collimation data, fit model and implement.
      1. run the focus/collimation routine dofpia at a range of elevations. Ask the telescope operator to slew. When the pupil is well collimated, note the filename. Make two lists, one for each side, of the names of these files with well-collimated pupils, e.g. bluecollimlist and redcollimlist
      2. For these files, run hselect to extract the mirror position, elevation and temperature filename: hsel @bluecollimlist mirrorx,mirrory,mirrorz,mirrorrx,mirrorry,telalt,lbttemp > bluecollimdata. There is an IRAF script, pcollim.cl which takes as input the list of fits files to be used for the collimation table and outputs the information, ready for input to the IDL fitting routine. The script adds 0.8mm to the mirrorZ values and it converts telescope elevation to decimal degrees. To run the script, define it as a task by giving the full pathname to the script file, i.e. at the IRAF prompt, type task pcollim = /path/to/pcollim.cl. It requires as input the name of the list of files with well-collimated pupils and an output filename, e.g. pcollim @bluecollimlist bluecollimdata.
      3. Run the idl procedure, mkcoll_lbc.pro (in /home/lbcobs/Collimation/new/), with the syntax mkcoll_lbc, "bluecollimdata". This will output a file called Collimation_lbc.dat which contains quadratic fits to X,Y,Z,RX,RY as functions of elevation and a set of plots.
      4. Edit the filename to be more descriptive (e.g. SXcollim_yymmdd.dat or DXcollim_yymmdd.dat).
      5. In the five lines around 0 degrees elevation (from +/- 0.2 degrees elevation), if there are any X,Y,Z values >2.0mm or <-2.0mm, replace these by 2.0 or -2.0 and if there are any RX or RY values >50 or <50 , replace these with 50. This prevents the mirror from bumping the static supports when parked at horizon.
      6. The following four steps are from the Commissioning/CollimationModel wiki. Move the new table into the right place/name where PSF will find it. As of 14-Dec-2010, the file with an appropriately coded name SXPMLBCCollimation.dat or DXPMLBCCollimation.dat goes in /home/telescope/TCS/Configuration/PSF/.
      7. Press the initialize button on PSF to load the new table. Be sure that Active Optics corrections are cleared and Global Offsets are cleared (green numbers are zero).
      8. Then it should work. Note that a small change in temperature can result in a different initial focus. The new table should be good enough for LBCFPIA to run without manual intervention. Verify that the new table isn't causing the mirror cell to "saturate" its position (X,Y,Z more than +-2.6 mm, RX,RY more than +-100 arcsec) at high or low elevations.
      9. Confirm that the new table gives correct results.

-- OlgaKuhn - 01 Jul 2011
Topic revision: r1 - 01 Jul 2011, OlgaKuhn
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