My third attempt at imaging this comet. Since I missed the critical time period where the comet was closest to Earth, I was forced to try one more time, but this time with an almost full moon just a few degrees off the target, which I think has washed out some of the detail I was hoping to get.....like the tail. On top of the moon, I had clouds rolling in, and of 904 sub exposures I rejected 422 of them due to very low point spread function numbers.
Anyway, I guess I'd better post it since this is the only image I managed to acquire.
Since this was my first comet, it was a voyage of discovery. Two really key points are:
- You can't set up an ASIair Plus to capture the comet three or four hours later in the middle of night without first working out exactly where it's going to be. I thought that the ASiair would calculate where the comet would be. But what happened is that I imaged an area of space that had absolutely nothing of interest in it. That's where the comet was when I programmed the ASIair Plus.
- PixInsight's CometAlign function doesn't like data with a meridian flip in the middle of it. It calculates the position of the comet via an extrapolation of velocity based on the first and last images captured. But with a meridian flip in the middle of data it gets confused and calculates the wrong speed, which of course then screws up the comet alignment.
Chris
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