I decided to re-do these measurements because the previous aLOG-38213 seemed to have really bad noise associated with the contour plots for ETMY, I think from one of the ALS loops still being active and  trying to lock which flashed some extra light onto the HWS periodically and screwed up the images.

Note: It is a bit difficult to adjust PZT2 to a point where we only saw the ETMY reflection (ETMX still works well), so it seems like the values measured by Nutsinee in aLOG-35979 are no longer valid.  I also found it difficult to search for the new offsets needed so Sheila suggested changing the green QPD offsets instead while the PZT servo was in-loop to make the measurement more repeatable:

- H1:ALS-Y_IP_ANG_YAW_OFFSET = -750 cnts

- H1:ALS-Y_IP_ANG_PIT_OFFSET = 840 cnts

- H1:ALS-X_IP_ANG_YAW_OFFSET = -1000 cnts

We also turned off the PLL locking so that ALS doesn't try to lock as well.

I've attached the first 180 secs after power up, there seems to be some absorption present but no obvious point absorbers.  However, the things to keep in mind are that the ALS-ETM sampling spot size is only about 5 cm in diameter and the overlap with the resonant IR beam is assumed based off the locking process to get up to DC_READOUT and there could be a more precise way to get better overlap between the two beams.

DC_READOUT: 2017-08-29 03:30:00 UTC

NLN: 2017-08-29 03:43:00 UTC