Summary
Today I tried pico'ing CO2 Y to get the CO2 beam better overlapped with the interferometer beam. The current status is the annular CO2Y beam is kind of close to the interferometer beam, but the annular CO2 is misaligned. I need to fix the alignment using the on-table pico but so far have been unsuccessful.
How it happened
It took me a while to realise that this afternoon I was driving the wrong pico motor. This could all have been avoided if I followed the steps on the medm screen. When I started the pico's, they had not been used since a Beckhoff reboot. The text on the current picomotor said "y top periscope mirror" and the x and y values for the "current motor" were (-8250, -4500) where Camilla had left the y top periscope mirror. However the "current motor" was 0 (which cannot be), and using time machine to look back (first attachment), the green lights were actually over picomotor 1. So the whole time I had been pico'ing on the table before the power control half waveplate!
Trying to recover on-table alignment with pico 1
Daniel pointed out that channels exist for each individual motor's current position (not just the current motor as is shown on the medm screen). Trending H1:SYS-MOTION_C_PICO_G_MOTOR_1_{X,Y}_POSITION, we saw that I moved motor 1 from (0,0) to (7500, 4500). I walked it back to (0,0) and thankfully the annular CO2 mask looked pretty well aligned on the HWS.
I thought I was out of the woods and could just proceed with picoing the top periscope mirror, however seemed like this excursion caused the central and annular CO2 masks to be misaligned from each other - see second and third attachments. I moved tried moving pico1 in both negative x and y but so far have been unable to recover the alignment. I'll have another go tomorrow.
Here's a video of ITMY HWS during a 5 minute central CO2 blast. The pico positions are (0,0) for the first steering mirror (pico1) and (-6250, -2500) for the top periscope mirror. It looks like it's clipping on something on the right, though as the optic heats up more it starts looking a little better.
Looking over the (many) screenshots I took yesterday during my pico mix-up, I think I need to move the first steering mirror in the +X direction to move the spot left.
Today I tried some more pico'ing for CO2Y. I moved pico3 in the x direction from -6250 to -2500. It still looks like when the beam is going through the central mask it's clipping on an edge on the right. I then checked the annular mask to see how well it was overlapped with the central, I tried a small move of pico1 (the first mirror before the hwp) but didn't see much change. It might be easiest to use the on-table camera to align through the masks and the pico+hartmann to center on the test mass, using pico and hws for both setting the beam through the masks and aligning onto the test mass is pretty confusing.
