I caught a break in this almost two week cloudy, showery, foggy spring weather pattern and managed to get the telescope over to the local Donovan elementary school on Friday night. While clear there was high cirrostratus and transparency was poor. I decided to try my hand at M3 and M13. Both are near the zenith between 10 and midnight.
Last winter the Meade 1697 computer drive system needed a repair and I opted to have it upgraded to an AutoStar I. I have mixed feelings about the Autostar. The good news is that alignment and tracking appear to have improved. I rarely have to spend as much time as in the past getting the GEM aligned with Polaris. On the other hand Autostar's usability and documentation is abysmal compared to Meade's original #497 controller. The menu system has become deeper and adds extra annoying steps.
That rant said Friday's results were a mediocre start. Using Arcturus I got rough focus. I then moved over to M3. I fine focused on the globular cluster using 1s preview exposures. In color mode the image had a very orange cast which I hope has to do with all the sodium vapor light pollution scattering off the high clouds and smog. I decided to image in B/W.
To my disappointment I was only able to use 2 to 4 sec exposures because of the severe periodic error. I guess my next night out will be devoted to learning how to and tuning PEC.
The focal end of the scope was getting dangerously close to a tripod leg during my M3 imaging session. Rather than chasing M3 to the other side of the GEM I moved to M13 which was now near the zenith. Again with M13 tweaked into focus I tried imaging the globular in B/W and color. Again the color images featured an orange cast and washout of the brightest stars. I'm not sure if this is a consequence of imaging in JPEG. I'll try using FitsInt, Fits or Fits3D
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