From initial alignment data, we know the following:
Positive offset in PIT (H2:SUS-ETMY_M0_OFFSET_P and H2:SUS-ITMY_M0_OFFSET_P) will tilt the mirros such that the reflected beam off of the mirrors will go down.
Positive offset in YAW will tilt the mirrors such that the reflected beam off of the mirrors will go toward the inside of L.
That is, the upper stage of ITM looks like the mirror image of the ETM. Why is this the case? I thought that they are identical.
Also, I think oplev sign is somehow wrong. It's not consistent with initial alignment data.
FYI, the sign of the things in initial alignment was figured out by:
First using baffle diodes to figure out the sign of the TMS to figure out the TMS sign, and make the first beam hit the center of the ITM.
Then using ETMY cage and CCD camera, make the reflected beam from the ITM hit the cage bars to figure out the sign of ITM.
Then move offset of ETMY so that the beam comes back to the table, then move TMS and repeat, to see if ETMY sign is the same as TMS (it is).
As you can see, there is not much ambiguity there.
Attached is the oplev and upper stage offset. (Jumps not caused by the offset are from HEPI.)
For positive SUS offset, the following is true for Oplev:
From this, oplev seems to think that positive PIT offset moves ETMY down but ITMY up, and positive YAW offset rotates both ETM and ITM in the same direction.