[DanH, Jenne]

We have turned on the dither alignment for the OMC once again. 

Prior to the vent and addition of the shroud, the dither alignment was trying to drive the OMC suspension farther than the range of the actuators.  We gave it a try again today though, and it worked just fine. 

We used /opt/rtcds/userapps/release/omc/common/scripts/ditherDCsense.py to measure the DC sensing matrix, and write the calculated input matrix to OMC-ASC_DACTMAT. The matrix was somewhat different.   The servo filters and gains are unchanged, with the exception of the OMC-ASC_MASTERGAIN, which is now 0.05 (was 0.1 when using the QPDs). This is the same gain value that was previously used for the dither loops.   

The offsets in the OMC QPDs have been set so that they will servo the OMC to the same place as the dither servos, so that they agree. 

We didn't see any change in the ~300 Hz bump, even though Gabriele did see the OMC alignment correlate with the size of that hump (alog 20555). 

The use of the dither servos is now back in the guardian.