I keep taking the same image with different cameras and telescopes looking for the "best." It never happens. I can't afford time on the Hubble Space Telescope.
However, I am getting better using PixInsight to process my images.
Messier 5 (M5, NGC 5904), contains roughly half as many stars as M13 and is actually a bit larger at 163.7 ly across than M13 at 134.7 ly across (depending on which "facts" you read). Being much farther away, it doesn't have that "sparkle." M5 is one of those globular clusters that makes one think it is the remanent of a dwarf galaxy that merged with the Milky Way. The average distance between stars in M5 (probably just considering the outer shell) is about 1.5 ly compared to the average 3 ly distance between stars in our vicinity. The outer halo of stars extends out to about 15 arcminutes. The image here is about 32 arcminutes vertically, so pretty much all of the halo stars have been captured.
The nearby double star 5 Serpentis is separated by 11 arcseconds. It would take a much lower exposure to resolve them, and could easily be done with this setup.
M5 was first documented by Gottfried Kirch and his wife Maria Margarethe in 702, then later independently discovered by Messier in 1764. Messier didn't think this "nebula" contained any stars. William Herschel resolved individual stars in 1791, but only counted about 200. The core was too dense to be resolved with his 40ft reflector.
Using an Atik Infinity in Prime Focus on my C14 almost completely resolves the core. (See:
https://www.astrobin.com/idbjz9/B/) The Infinity doesn't have the resolution of the 490, so the stars look at bit more bloated with the Infinity.
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