Eastern Veil Nebula
This a narrowband image of the Eastern Veil (also known as Caldwell 33), whose brightest area is NGC 6992, which is part of a much larger nebula complex known as the Veil Nebula, a supernova remnant. This image is created using data collected through Ha, OIII, and SII narrowband filters, to bring out complex details and enhance contrast. Since some of the wavelengths emitted are not detected by the human eye, and the object itself is too faint to detect visually, the colors are an artificial mix, created by arbitrarily assigned the different filtered wavelengths of light to visible colors of the spectrum. This 'mix' is just the one I found to be pleasing, and it also gives the charicteristic reddish colors for the Ha areas and the teal colors for the OIII regions. The color mix used is:
Red: 76% Ha, 24% SII
Green: 100% OIII
Blue: 95% OIII, 5% Ha
Equipment:
ZWO ASI1600MM-C Camera @ -15C and Gain:139 Offset:21
Software Bisque MyT Mount
Stellarvue SVQ100 Astrograph Refractor, 580mm @ f/5.8
Software:
Pixinsight Commercial Version 1.8
Lightroom CC
Photoshop CC
Light Frames:
Ha: 8 x 360 secs (48 mins)
OIII: 7 x 360 secs (42 mins)
SII: 7 x 360 secs (42 mins)
Dark Frames:
8 x 360 secs (48 mins)
More details from Wikipedia:
The Veil Nebula is a cloud of heated and ionized gas and dust in the constellation Cygnus. It constitutes the visible portions of the Cygnus Loop (radio source W78, or Sharpless 103), a large but relatively faint supernova remnant. The source supernova exploded circa 3,000 BC to 6,000 BC, and the remnants have since expanded to cover an area roughly 3 degrees in diameter (about 6 times the diameter, or 36 times the area, of the full moon). The distance to the nebula is not precisely known, but Far Ultraviolet Spectroscopic Explorer (FUSE) data supports a distance of about 1,470 light-years.[2]