Urban Bubble Nebula

Here is another urban image taken from my urban driveway. Consider it a COVID bubble here in Atlantic Canada.

According to Wikipedia -  NGC 7635, also known as the Bubble Nebula, Sharpless 162, or Caldwell 11, is an H II region emission nebula in the constellation Cassiopeia. It lies close to the direction of the open cluster Messier 52. The "bubble" is created by the stellar wind from a massive hot, 8.7 magnitude young central star, SAO 20575 (BD+602522). The nebula is near a giant molecular cloud which contains the expansion of the bubble nebula while itself being excited by the hot central star, causing it to glow. It was discovered in 1787 by William Herschel. The star BD+602522 is thought to have a mass of about 44 solar masses.

M5 was discovered by German astronomer Gottfried Kirch in 1702 when he was observing a comet. Charles Messier also noted it in 1764, but thought it was a nebula without any stars associated with it. William Herschel was the first to resolve individual stars in the cluster in 1791, counting roughly 200.

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Object NGC7635 (Bubble Nebula) RA 23:20.2 Dec +61:11
Date 18 October, 2020
Exposure 3.25 hours (13 X 15 minutes)
Conditions Bortle 6 skies, high light pollution levels.
ISO 1600
Camera Canon 60Da DSLR
Optics Prime focus of a  SkyWatcher Esprit 120 f/7 APO refractor with a focal length of 840 mm
Filter Optolong L-enHance
Location Bedford, Nova Scotia
Processing This image was captured using Sequence Generator Pro, telescope control provided by Mosaic Engine and processed entirely in Images Plus using my standard urban filtered image workflow. First the three colour channels were equalized using pixel math and levels. Next an arcsinh stretch was applied to the image to brighten it up. The feature mask was used to split the stars out of the image and the nebula layer was noise reduced with a masked detail preserving smooth and a masked low pass filter applied in the frequency domain. Next the nebula layer was sharpened and enhanced using multi-scale decomposition and a slight hipass filter applied in the frequency domain. The star layer had a slight gaussian blur applied and then recombined with the enhanced nebula layer. The image was cropped and binned by 2 for web display.