The next item in the catalog is M5, a bright globular cluster easily traced 7th, 5 southwest of Alpha Ser, visible through binoculars 10x50.
Like most of the brightest globular clusters cataloged by Messier, this one starts to resolve into stars, at least on the periphery, with an instrument of 13-15 cm.
With a 30-cm reflector is obtained in a yield visually spectacular shows of good seeing. The density of this globular cluster near the center is so high that the stars in complete resolution instruments is restricted to about one meter.
In a medium or long exposure photography, the remarkable concentration of stars in the cluster center turns almost uniform and white image, as overexposed: This problem affects nn instead the amounts taken by the CCD, if properly treated.
Image of M5 by wikipedia
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