While poking around looking at screens in the control room this morning, I noticed the ETMx OL sum is was low. Some trends reveal that there was a drastic drop of the laser power on the QPD on Sat morning. A trend of ETMx signals, as well as some ISI and HEPI signals (not shown), indicate those systems are ~healthy. So, it does not seem that the physical pointing of the ETMx via SUS or SEI has changed the pointing on the OL. Note, this happened a day after the Fri EQ which caused all the ISIs to trip. Likely we should investigate the OL itself to see what's going on with the laser beam/QPD.