M5
Globular cluster M5 is apparently small and visible to the naked eye only as a faint star. Its brightest stars reach approximately 12th magnitude. The age of the star cluster is about 13 billion years, so it is one of the older star clusters of the Milky Way. Located approximately 24,500 light-years from Earth, it contains more than 100,000 stars, with some estimates as high as 500,000. 105 variable stars were discovered in it, of which 97 belong to the RR Lyrae type. These regularly pulsating variable stars are similar to Cepheids and can be used to measure distances in space because the relationship between their luminosity and period length is well known. The brightest and most easily observed variable stars in M5 have an apparent magnitude of 10.6 to 12.1 and vary in luminosity with a period of less than 26.5 days.
I did not manage to calibrate the flat images properly, so only the detail of the star cluster is used. Still, ISO 400 allowed a very nice color rendition of the stars.