Thursday, May 28, 2009
Observing Report: May 27
The night began as predicted. Storm clouds rushed in and sat overhead for the first hour or so. Once they cleared, and the weather predictions indicated that no more fronts were approaching, it was time to open the dome. Seeing was decent throughout most of the night. It wasn't until about 2:30a that things deteriorated. Seeing became horrible. Some sneaky cirrus clouds may have moved in unnoticed, I am still not entirely sure, but even at low airmasses the seeing was around 1.8" compared to the usual 1.2"->1.5". I tended to focus on objects that were yielding good images without adjusting the focus on the telescope since that can be a time consuming process. Once again the clouds hampered any opportunity to take evening twilight sky flats so I will once again be up a bit longer taking dome flats. Although I could more than likely use flats from other nights, since the detector has been kept at a constant temperature (-120 C), it is better to be safe than sorry and have dome flats on reserve just in case the sky flats from various nights highlight different detector characteristics. Aside from the clouds, no technical problems were encountered, thankfully!