Other Names: Caldwell 27, SH2-105
Optics: Meade 10" ACF SCT at f/9.4
Mount: Paramount MX using The SkyX Pro
Camera: QSI 683WSG-8
Filters: Astrodon Ha 3nm
Exposure: 1990 Mins or 33.17 hrs, 1800 & 1200s exposures, Binned 2x2
Accessories: Auto guided with Starlight Xpress Adaptive Optics, Starlight Xpress Lodestar & PHD2.
FLI Atlas focuser using FocusMax 4.1.0.72
Location: Burlington, ON, Canada
Date: Taken over several nights from August 5th, to September 22nd, 2017

Notes: data was acquired using TSX Pro and MaxPilote automation software.
Processing: Image calibration, & align in Maxim DL Pro. Levels, curves, cosmetic adjustments and crop/resize in Photoshop. Calibrated w/32 Darks, 100 Bias, 50 Flats using natural sky flats. CCD temperature was -20C & -25C depending on the night. Image was taken from my backyard Observatory.

Link to Bi-Color Version: https://astromarina.zenfolio.com/p52895960/hc00d165c#hc00d165c

The Crescent Nebula is an emission nebula in the constellation Cygnus, about 5000 light-years away from Earth. It was discovered by Friedrich Wilhelm Herschel in 1792.[2] It is formed by the fast stellar wind from the Wolf-Rayet star WR 136 (HD 192163) colliding with and energizing the slower moving wind ejected by the star when it became a red giant around 250,000[3] to 400,000[citation needed] years ago. The result of the collision is a shell and two shock waves, one moving outward and one moving inward. The inward moving shock wave heats the stellar wind to X-ray-emitting temperatures.