Lorenzo Comolli's Astronomy HomePage

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Here is the king of the globular clusters! Any comparison with the pince of the northern hemisphere is useless, simply there is nothing to compare. :-) The first time I've seen it was with a 50 cm dobsonian telescope under the perfect sky of Tivoli Farm, Namibia, I've promised that I'll never lost again my time for observing such a small object like M13...

For a comparison of the 6 best globular cluster of the whole sky, look at "The best globular clusters"; or for only Omega Cen - M13 comparison look at "Comparison of Omega Centauri and M13".

Technical Data
Optics	Takahashi FS152 apo refractor
Focal Lenght	1216 mm (direct focus, no flattener)
Focal Ratio	f/8
Exposure Time	1h30min (single exp of 10 min)
CCD	Canon EOS 5D with Baader filter
Sensitivity	800 ISO
Location	Tivoli Farm (Namibia) at 1350 m height
Date	28 August 2011
Mount	Fornax 51
Tracking	SXV-H5 on a Vixen 80/640 apo refractor
Temperature and humidity	T= 15 °C, RH= 27 %
Sky brightness at zenith (with SQM-L)	21.6 mag/arcsec^2
Notes	This image is a collaborative effort of the Namibia 2011 expedition. Processing: Lorenzo Comolli. Images by: Lorenzo Comolli, Luigi Fontana, Giosuè Ghioldi, Emmanuele Sordini.