Yesterday Camilla and I put two irises on the FCGS refl path, 89751, to use as a reference for FC1 alignment, and turned on the cleanroom to test how well this would work.  The temperature swing in zone 4 G was not as large this time as other times that the cleanroom was turned on or off, but it is large enough for us to see.  Around 11:30 this morning I went to the table to check the iris, the beam was off as shown in the photo.  I walked it towards being centered on the iris, and this recovered the green flashes to 40 counts, with CLF locked IR flashes are up to 0.4-0.6, infrequently, and frequently around 0.2 counts.  

While I was doing this, I saw that when FC1 was badly misaligned, looking at the green here is a nice way to see where the filter cavity flashes are, movie attached.  

This screenshot shows what this looked like on the osems and sliders: I moved FC1 +10 urad in pitch on the slider by looking at the iris, which restored the flahes.  The top mass osem suggests that after this adjustment FC1 pitch is undercorrected by -43urad, M2 wit would suggest that I overcorrected by  +4urad, M3 wit says I overcorrected by +10urad.  

Here's a screenshot of all osems earlier in the week with Camilla had nice flashes in IR and green, and here's a screenshot of all the osems now.