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 There
            are three relatively bright globular star clusters in this constellation,
            M13, M92 and this one. Rated at a much dimmer 9.4th magnitude
            and a diminutive 4.5 arcminutes in size, it is certainly outclassed
            by the brighter members of the trio, yet is rarely shot by amateurs.
            It is difficult to resolve, the stars are dim - typically 15.5
            magnitude but most being 18th and dimmer. Close examination of
            the largest image will show a sprinkling of blue dim stars on
            the periphery of this cluster, the orange supergiants dominating
            the scene because of their much brighter magnitude. Little resolution
            in the core is seen, even with the 12.5 inch. 
Instrument:  12.5" f/5 Home made Newtonian
Platform:  Astrophysics 1200 QMD
CCD Camera:  SBIG 10XME NABG with Enhanced Cooling
Guider: SBIG ST4
Exposure:  LRGB = 60:20:20:20
RGB Combine Ratio:  1: 1.05: 1.11 (G2V)
Filters:  AstroDon RGB Tricolor
Location:  Payson, Arizona
Elevation:  5150 ft.
Sky:  Seeing FWHM = 5 arcsec (Maxim DL - 10min subframe), Transparency 8/10
Outside Temperature:  15 C
CCD Temperature:  -30 C
Processing Tools:  Maxim DL,  Photoshop, PixInsight, CCDOps Debloomer.
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