A bit of a frustrating morning.
Since Alignment was decent enough to get through DRMI, I opted to look at Input Alignment again. Patrick pretty much restored the IM4 Trans Pit/Yaw to where they should be (good thing!). I thought the yaw could be moved a little more though. I decided to move the IM3 in yaw a bit. (Talked with Kiwamu and he felt this was good to try).
Since the input pointing was changed, I then started an Initial Alignment. Unfortunately, I ran into issues at the beginning with ALS. I could have sworn both ALSx & y were fine at first, but after waiting a few minutes for control signals to converge, I noticed ALSy was in a completely bad alignment state. I spent way too much time trying to get an alignment back, could never get much above 0.5 & when I did WFS drove the alignment off. After talking with Kiwamu, he suggested taking guardian to LOCKED NO SLOW NO WFS & tweak on ITMy & ITMy. Finally, made some progress here and took the arms up to 1.05, went to INITIAL ALIGNMENT (which enables wfs), and Y-arm looked great....
...but then ALSx all of a sudden looked ugly. It had a 0:0 mode, but it's power was oscillating from 0.4 -0.8 with a period of 6-7sec. (on the Tidal strip tool, the ALS x & y REFL control signals are oscillating with this period. useism doesn't look bad (under 90 percentile & there's no wind). Asked whether the tidal issues Patrick had last night could be an issue here, but since we aren't fully locked it should not. So moving on...
Oh, and within a few minutes, I lost ALSy again!!
SO: Going to work on ALSx & then ALSy (probably with no WFS). Kiwamu said another knob I can use is the ALS WFS GAIN for each arm, if needed.
OK, back at it.
Just further notes. I initially did move TMS when working on the Yarm, but then I returned it to its OSEM values. BUT, after tweaking only the ITMy & ETMy, I see that the TMS OSEM values have drifted a bit. Maybe this is standard, but I was surprised at that.
Hey Patrick! Sorry, I've not been able to recover what you did last night. Well, Kiwamu will be on site in a bit---I was just wanting to figure this out! :-/
Other ALS notes:
At this point now, the ALS spot is really ugly (and this is after returning sliders to original values
Oh, and another odd effect is how AS AIR video looks. there's a couple of spots which look like they are rotating through every few seconds (I've not seen that before).