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Automate TCS offset calibration using ACAM images #41

Open chazshapiro opened 1 year ago

chazshapiro commented 1 year ago

The default offsets on the P200 TCS periodically (nightly? after resets?) need to be calibrated and "zeroed". We should be able to do this using the ACAM. There needs to be an automatic (or very easy + documented) procedure for doing so.

Steps:

  1. Choose target to center on ACAM (have a list of good targets)
  2. Use FPoffsets to solve for scope coordinates (acam to scope) -- same as when doing this for a target from the list
  3. Slew to scope coordinates -- target should be visible in ACAM but not centered.
  4. Do acquisition sequence with offset upper limit removed
  5. Once target is acquired, the resulting offsets should be logged, then zeroed out in the TCS.
  6. Repeat acquisition to verify offset is ~0; might as well log and zero the offsets again.
  7. Reinstate offset upper limit

If the required offsets are very large (several arcmin) the acquisition may fail. Then we need some manual procedure involving e.g. astrometry.net for step 4-5.

chazshapiro commented 9 months ago

If a target field is solved during acquisition but with a large offset, this effectively accomplishes the above, except we normally prevent large offsets. We could have some exception to the rule or put a warning in the text box that uses the last solution to zero the offsets.

jenniferwillow commented 9 months ago

Hi Dave, Chaz

 I had another thought.  It looks like this procedure is identical to acquiring a target except that the upper limit on the offsets are removed.  Maybe we just put the system into “calibration” mode (and make this a command that can be sent by the OS).  On considering this again, all of the telescope motion commands are sent by the OS so I’m not sure how this should be assigned to the ACAM system?  I think this is really a procedure that needs to be implemented in the OS and not part of ACAM.  None of the actions in this list are really actions for the ACAM beyond supporting the functions that it already does (i.e. acquire images and return the file name).

Sincerely, Jennifer Milburn

On Sep 14, 2023, at 10:33 AM, Chaz Shapiro @.**@.>> wrote:

If a target field is solved during acquisition but with a large offset, this effectively accomplishes the above, except we normally prevent large offsets. We could have some exception to the rule or put a warning in the text box that uses the last solution to zero the offsets.

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