Decided to get up early this morning to attempt to take some comet pics. The comet is getting higher, it rose this a.m. around 3:30 a.m. and by 4:30 was high enough for me to get an image. Unfortunately the aperture of the telescope was between 1/2 and 1/3 blocked when the above pictures were taken.
The RCX did not seem to take too kindly to the camera load this morning as tracking seemed to be way off. I used a sequence of 3 - 10 second exposures through each color wheel and then aligned them on the comet's coma. Since the comet is moving rapidly, its orientation to the background stars changes between each exposure, so there are "lines" of stars all over the image.
No autoguiding or even manual guiding was attempted. Partly because I'm lazy, partly because there just isn't much time before the twilight takes over and makes the tail disappear. It would have been better to take longer exposures while guiding on the comet's nucleus region. A longer exposure might have brought out more detail in the tail.
Note that the tail is currently being reported as being about 3 degrees long - this field of view is only about 18 arcminutes long!
One of these days I'm really hoping to figure out a way to piggyback a nice refractor to do separate guiding, which should solve several of my problems. At present there is a severe lack of available accessories such as mounting rails for the RCX scopes, I hope that changes soon.
In addition to the combining, I did a limited amount of "processing" to try to enhace the image, such as stretching the color curve. However since my knowledge of the various processing methods is limited, it's mainly just a dump of the various data sets. I really need to learn more about the post-acquisition processing phase. I have the new Scott Ireland book, Photoshop Astronomy, that I need to read and practice with to learn how to get the most out of my data.
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