This morning Pablo and I worked on getting (separate) cameras on both of the arm transmitted beams on ISCT1. We approximately followed the layout posted in llo alog 12198

To do this we had to add a lens in the Y arm path before the pick off for a camera, we used a Laser Optic +50mm roc. We used R=10% beam splitters for the pick offs for the cameras. We used analog cameras temporarily.  I borrowed the POP cable (labeled POD) for the X arm trans camera, and used the REFL_PD camera that we have been using for the X+Y arms for the Y arm.  The Y arm spot is on a baffle, the camera has a lens and is focused on the spot on the baffle, this makes a nicer image where we can clearly see the different cavity modes.  We will do this for the X arm camera as well once we find a good lens. 

Once we saw that both arms had nice IR flashes, I worked on aligning the diff beatnote.  On the diff BBPD we have about 126 uW from the Y arm when it is locked and about 40uW from the X arm.  We get -30dBm on the beatnote, (at 160MHz) I din't really try to optimize this since the cavity keeps dropping out of lock making it difficult to adjust.