Showed that not only were conditions quite favorable for clear-sky observations, the rest of the week would be obscured by clouds. So it was now or never, to overstate the drama a bit. The only drawback would be that temperatures would drop below freezing. For this Texas boy, that's a significant obstacle to overcome, but I made the effort.
During my ill-fated eclipse shoot last week, I had major halation issues with the type of eyepiece projection photography I was attempting, so moved the primary mirror of my telescope up several inches for prime astrophotography. The resulting lunar image was very, very sharp and I wanted to experiment some more. Unfortunately, by the time I made the decision to set up, the sun had already gone down, and in the poor lighting conditions my polar alignment of my scope was mediocre at best. Good polar alignment allows long time exposures of the night sky, as the motor drives the telescope to track the sky as it appears to move overhead. Early test shots of the Pleiades and Orion Nebula was disappointing. Achieving accurate focus through the camera was exceptionally difficult, but even worse, exposures longer than 5 seconds resulted in stars elongated into streaks. Again, poor polar alignment.
Eventually I gave up on shooting any Deep Space Objects, and decided to wait for the moon to rise. Checking online, I expected moon rise at around 11:30, and figured I could shoot by midnight, or 12:30 at the latest. Turns out I got sloppy and looked up the pacific timezone table or somesuch, because it was 12:30 before the moon started peeking over the rooftops of my neighborhood. I was tired, cold and cranky by that time, and couldn't even entertain myself by random astronomical observations, because, you know, prime focus and all that. Eventually, I got this shot, and broke everything down by 2 a.m.
The shot above is the best of approximately 50 shots. Unlike my sharp pre-eclipse photo last week, with the air still and clear, the moon this night was still fairly low in the sky, and turbulence was rampant. Through the scope, it appeared as if the sky were boiling in front of the moon, and distorting it as you might expect. The trouble is that the turbulence causes focus to come and go. I had to discard many shots in which southern craters were very sharp, but northern mountains were fuzzy. Or the mountains were sharp, but the lunar horizon was blurred. It was a mess. Waiting until the moon was at the zenith might have cured those problems, but then again, might not. I wasn't about to stay up until 4 a.m. to find out. I'll get some better lunar photos some day, but until then, this will have to do.
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