M13 is a globular cluster in Hercules located about 25,000 light-years from earth. It contains several hundred thousand stars packed into a space 145 light-years in diameter. The density of stars is so high that they sometimes collide producing new stars. Near the core of M13, 100 stars could be contained in a cube 3 light-years per side. In comparison, our sun's nearest neighbor, Proxima Centauri, is over 4 light years away. When I look at M13, I am reminded of the line for the Novel 2001: A Space Odyssey - "My God, it's full of stars".
I am revisiting this subject after imaging it about a year ago to correct one major short coming. The ASI 1600 produced "interesting" micro-lens artifacts on bright stars that I never really liked. I tried removing them but eventually just accepted them. See
https://www.astrobin.com/sguhw2/B/?nc=user for my previous attempt.
My latest version of M13 uses the ASI 294MM Pro which happily does not produce these colorful spikes. Other notable changes: I moved this telescope into my remote observatory in the Patagonia Mountains and I am am using an upgraded field flattener with my SVX 130T. For this one I used no sharpening beyond deconvolution. But I did take my Luminance data using the 294's bin 1 mode. I am a little under sampled at bin 2 but way over sampled at bin 1. The result is sharper and smaller stars in M13.
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