M3 – Globular Cluster Canes Venatici

Telescope: Meade N6 at f/5, Orion Atlas EQ-G
Camera: Full-spectrum Modified Canon 600D, Orion Imaging Skyglow Filter
Guide scope: Williams Optics 50mm, Meade DSI Pro III, PHD
Exposure: 16x45sec ISO 800 saved as RAW
Darks: Internal (Long Exposure Noise Reduction On)
Flat: 32x1/250sec, ISO 800, tee shirt flats taken during twilight
Average Light Pollution: Red zone, fair transparency
Lensed Sky Quality Meter: 18.6 mag/arc-sec^2
Stacking: Mean with a 2-sigma clip.
White Balance: Nebulosity Automatic
Software: Backyard EOS, Nebulosity, Deep Sky Stacker, Photoshop

I squeezed this one in at the end of a recent all-nighter (the evening of November 23rd) when I had just a few minutes of night left before the start of morning twilight. What’s neat about the source images is that I can see the moment sunlight begins to illuminate the upper atmosphere through which I am imaging.

Neat stuff.

-John

M3 (11-23-2017)-1j.jpg