|Oph||16h47m / -01°57'||16'||6.1mag|
|The globular cluster Messier 12 (NGC 6218) in the constellation Ophiuchus,
photographed on May 12, 2018. Messier 12 is approximately 16'000 light-years from Earth, measures about 75 light-years in diameter
and was discovered by French astronomer Charles Messier in 1764. The cluster is only loosely packed (source: Wikipedia).
Twenty-two exposures of 3 minutes at ISO 800 were stacked with no dark frame subtraction with Deep Sky Stacker (resulting in a 1 h 6 min exposure) and further processed in Photoshop.
|Equipment: Canon EOS 450D Baader modified camera, TeleVue Paracorr Type II coma corrector, 16" f/4.5 "Ninja" dobsonian telescope riding on a dual-axis Tom Osypowski equatorial platform, Lacerta MGEN autoguider, Lacerta off axis system (field of view comparison: image of the moon with the same equipment).|
Search chart for Messier 12. Map © 2018 "The Mag-7 Star
Atlas Project", www.siaris.net. Map is modified. The Mag-7 Star Atlas Project map can be downloaded
You can improve your deep-sky object search skills here .