PEPSIPOL 20170920 UT


We had 2 hours of horrible seeing tonight (20170920 UT) so we worked on the list of PEPSIPOL things to do. Status below.

On Thu, Sep 14, 2017 at 07:17:59PM -0700 or thereabouts, John Hill wrote: '> Dear AO guys,

'> We didn't get to finish all the start-up activities related to PEPSI active optics during start-up observations. Yes, the seeing was so good during start-up that it was the "bad-seeing projects" that didn't get finished. Thus, I'm planning to be your bad seeing backup program during next week's LUCI-AO activities.

'> The particular activities are

'> 1) DX PEPSIPFU - adjust DX M3 Tip to align pupil on S-H wfs.
'> (30 min) JMH or DLM

We tried this, but the back illumination fiber was left on, so we couldn't guide on a real star.

'> 2) Both PEPSIPOL - Confirm off-axis guiding
'> (30 min) JMH

We successfully guided off-axis with SX. The AGW4 guide probe won't move so nothing on DX. See Issue 6786. Both sides have now guided, but not at the same time.

'> 3) Both PEPSIPOL - Adjust pupil configuration params for active optics
'> (1 hr) DLM

The basic parameters for pupil position on the S-H array are set, but could use refinement once we are well collimated.

The main things remaining to do are:

a) to adjust WFS_rotAngleOffs to rotate the Zernikes into the frame of the primary mirror. ~30 mins with JMH and DLM. The seeing was too noisy to finish this tonight.

b) to adjust the direction of the non-telecentric pupil shift as a function of field position. (offline once we have wfs images for a few guide stars around the field)

'> 4) Refine the X_ZEROPOINT rotation angles once collimated (1 hr) JMH

We checked this on one star 200 arcsec off-axis. At the level of 1 part in 50, the SX angle is correct. More refinement would require centering the AGW probe to the rotator axis which we have not done. Perhaps better to check the angle with the polarimeter camera.

'> Once those are done, our next bad seeing activity would be to collect
'> more pointing and collimation data.


AGW4 not moving See IT 6767, 6768


09:31 ACTIVE preset AGW3 off-axis

09:51 ACTIVE preset AGW3 on-axis

10:02 ACQUIRE on-axis; ACQUIRE off-axis

10:15 ACTIVE on-axis blocked --- -957 Z5, +642 Z6

10:22 +2000 Z6 ---- -21xx Z5, +37 Z6
0 Z6, 135 SFP_ROT --> 90; ---- 91 Z5, 1242 Z6

10:37 +2000 Z5 ---- +514 Z5, -680 Z6

10:38 0 Z5 ---- +1691 Z5, +40 Z6

still the same - noise is +- 1000 nm

10:42 +4000 Z6

10:46 Restart GCSL

10:49 Send +1000 Z7 measure -671 Z5, 0 Z6

10:50 Send +2000 Z6 measure +726 Z5, -1628 Z6 still very noisy

10:52 Remove Z6 measure +658 Z5, -201 Z6

10:53 Send +1000 Z7

10:56 Switching back to LUCI

Doug wfsc.rotoffset ----> wfs_rotAngleOffs (new value = 34 deg)

ToDo - see IT 6845

  • Fix paddle (Done by Steve 20171014)
  • Fix Newpoint
  • Fix pupil shift direction
  • Probe Rotation Factor
  • Probe Center

-- %USERSIG{JohnHill - 2018-04-10}%
Topic revision: r3 - 24 May 2018, JohnHill
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