NGC 6888 - The Crescent Nebula (63hrs)

[Mr_42tr0nomy]

It's been two months in the making. And despite vacations, crappy weather, and equipment reconfiguration, I'VE FINALLY FINISHED! This image consists of 30 hrs each Ha and Oiii (3nm) as well as 1hrs each of RGB data for the stars. I shot the RGB data the past two night during the full moon so a little more data was needed. I originally thought 30 min each would do the trick but 1hr each produced much more colorful stars. This is my longest project to date so I tried to be pretty meticulous when it came to post processing, especially in getting that outer Oiii shell to show. I call it the energy shield! Anyways, I hope you all enjoy!

The Crescent Nebula (Description by Nasa's APOD) - "NGC 6888, also known as the Crescent Nebula, is a cosmic bubble about 25 light-years across, blown by winds from its central, bright, massive star. This sharp telescopic portrait uses narrow band image data that isolates light from hydrogen and oxygen atoms in the wind-blown nebula. The oxygen atoms produce the blue-green hue that seems to enshroud the detailed folds and filaments. Visible within the nebula, NGC 6888's central star is classified as a Wolf-Rayet star (WR 136). The star is shedding its outer envelope in a strong stellar wind, ejecting the equivalent of the Sun's mass every 10,000 years. The nebula's complex structures are likely the result of this strong wind interacting with material ejected in an earlier phase. Burning fuel at a prodigious rate and near the end of its stellar life this star should ultimately go out with a bang in a spectacular supernova explosion. Found in the nebula rich constellation Cygnus, NGC 6888 is about 5,000 light-years away. "

Eqiupiment:
AT8RC
CEM60
ASI1600mm-pro
Astrodon HA/OIII/RGB
QHY5L-ii autoguider
phd, spg, pix, ps, dss

Exposure details:
180x600s (ha)
180x600s (Oiii)
60x60x RGB (ea.)

Dates:
7/4, 7/5, 7/6, 7/7, 7/9, 7/28, 7/29, 7/30, 8/1, 8/2, 8/3, 8/4, 8/6, 8/7, 8/11 8/12, 8/13, 8/14, 8/15,

[JamesF]

That's fantastic!  It looks so three-dimensional!

James

[Starwiz]

Spectacular!

A wonderful image.

John

[MartinFransson]

63 hours is nothing short of amazing!

How do you add the RGB stars to get a natural look?

[Mr_42tr0nomy]

I desaturate my stars in my Ha Oiii image and I over saturated my RGB image and I just layer then in photoshop using “lighten”. I then create a star mask in Pixinisght and saturate the color of the stars until I like them!