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West of Sadr, Mosaic

Cygnus West of Sadr, HaRGB

July 28th, 2017

For the past month I have spent over 20 hours capturing data and processing to form this image. It’s quite a relief to have it finished and I think I am happy with it. All this data was captured from my bortle 8 location in the city and most of the nebulosity in the image is extremely faint, with magnitudes in the 20’s and up. This is a true testament to the new camera.

The centerpiece of the image, the Propeller Nebula, is not actually cataloged but is near DWB 111 and is often given that designation. The bright star in the upper left is Sadr, the second brightest star in Cygnus and easily visible from the city. A closer look will reveal a gas cloud just behind the star. Left of Sadr is the magnificent butterfly nebula, known as IC 1318. To the right and up of Sadr is a blue reflection nebulae complex known as NGC 6914. Many other nebulae and clusters dot the image, which spans nearly 9 degrees from one side to the other. Hydrogen gas is shown here as pink/red.

Capture Details:

Captured on: 4 nights in July

Canon 200mm F/2.8L @ F/3.5
ZWO ASI 1600mm-C
ZWO filters
iOptron ZEQ25gt
Orion SSAG


Halpha: ZWO 7nm Ha filter(1.25″), 40x180s, -10C, Unity Gain (per frame)
Red: ZWO Red filter(1.25″), 30x60s, -10C, Gain 75, Offset 10 (per frame)
Green: ZWO Green filter(1.25″), 30x60s, -10C, Gain 75, Offset 10 (per frame)
Blue: ZWO Blue filter(1.25″), 30x60s, -10C, Gain 75, Offset 10 (per frame)

4 panels total (2×2)

Total Aquisition of 14hrs (my personal record)


Thanks for looking!