[Camilla, Jenne, Sheila, Keita]

Camilla had several locklosses at ENGAGE_SOFT_LOOPS again tonight.  Normally the remedy is to go back and do another initial alignment, but Sheila pointed out that in all of the lock attempts the Yarm isn't arriving at the engage ASC states very close to the correct alignment.  Since this has been true even after fresh initial alignments, this is indicative of the inital alignment setpoints not being very good. 

We checked, and this is not at all related to the camera network/freezing issues of late.  Every time the camera setpoints come back correctly to the values that were last changed at the end of October.  So, this is likely just that things have drifted over the last ~3 months and the initial alignment setpoints just needed updating. 

Since we had been failing to even engage the soft loops, we hand-moved the Yarm soft using the script ....userapps/asc/h1/move_ARM_dev.py in steps of "YS P 0.03" to get the ADS DOF 5 Pit a bit closer to zero.  When it was off the limiter rail (but not yet all the way to zero), we let the guardian finish the soft loop alignment to the centers of the optics by letting it do ENGAGE_SOFT_LOOPS.  Once all of the soft loops had converged, we checked that the Yarm green was resonating the TEM00 mode, and saw that the green WFS and camera values were not close to zero.  So, we ran the script ....userapps/als/h1/scripts/setEndGreenQPDOffsets_YARM.py to change the WFS centering setpoints, and once that was finished we also set the camera values. 

The Xarm green didn't want to catch the 00 mode, and since the Xarm ADS hasn't been a problem we elected to go forward with locking.  We lost lock later in the sequence, so did an initial alignment to confirm that we can reacquire with these updated Yarm initial alignment setpoints.  I have on the board to check the Xarm setpoints on Tuesday after maintenance.

Attached are screenshots of the new values, and the old values. 

Alog 50968 has a sketch of the procedure on how to update initial alignment references.