Cao, Dan
While installing the phase camera we noticed that the POP beam was being clipped on POP-BS2. After centering it we found we could not realign onto POPAIR B and get similar POP90 and POP18 build ups as we did previously.
Before centering we were seeing POP90~75 and POP18~55, after this was about 35 and 25. We could actually make the build ups significantly higher if we clipped the beam even more, as can be seen in the attached traces. We left the alignment so that the POP beam was not being clipped.