M3
Globular Cluster
M3
was the first Messier object to be discovered by Charles Messier (M1
and M2 were already known.) Boasting around 500,000 stars,
it measures 90 light-years across and is located about 34,000
light-years from Earth. It is
perhaps the most studied of the globular clusters.
Scope/Mount:
TS-Optics PhotoLine 130mm F7 APO Refractor with Astro-Tech AT2FF
Field-flattener, Celestron CI-700 Mount
Camera:
ZWO ASI1600MMC monochrome with ZWO LRGB filters
Guiding:
QHY5L-IIM through Orion Thin OAG, PHD guiding software
Exposure:
L (30) 120 sec @ gain=80, RGB: each channel (10) 120 sec @
gain=139
Software:
Nebulosity, PhotoShop CS2
Comment:
04-25-2020, Tierra del Sol, CA, good
conditions.