M27 with Optolong L-eNhance Filter

The Dumbbell Nebula (also known as Apple Core Nebula, Messier 27, M 27, or NGC 6853) is a planetary nebula in the constellation Vulpecula, at a distance of about 1227 light-years. This object was the first planetary nebula to be discovered; by Charles Messier in 1764. At its brightness of visual magnitude 7.5 and its diameter of about 8 arcminutes according to Wikipedia. This shot was captured using an Optolong L-eNhance light pollution filter. The filter darkened the background substantially allowing the very faint outer envelope of the nebula to be pulled out in processing. Unfortunately clouds rolled in and cut the imaging session short so I plan on adding another two hours at my first opportunity so the stretch can be pusher further to brighten the outer envelope. Click on the image to see a higher resolution version, then click again on the image to return to this page.

Object M27 RA 19:59.6 Dec  22:43 Date 17 Aug, 2020 Exposure 140 minutes (14 X 10 minutes) Conditions Bortle 4.75 skies. Occasional high thin cloud, but clear otherwise.  ISO 800 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 filter Location Marion Bridge, Nova Scotia Processing This image was captured using Sequence Generator Pro, telescope control provided by Mosaic Engine and processed entirely in Images Plus. An initial arcsinh stretch  was used to brighten the image followed by splitting the stars and nebula out to separate layers. The nebula layer was noise reduced with an application of a masked low pass filter in the frequency domain. Next the nebula was sharpened and recombined with the star layer. The colour was adjusted using the color balance tool sampling both the background and a white star. Levels were used to set the black point and a curves adjustment used to set the final contrast. Finally a deconvoluation with a small radius Gaussian was used to tighten the stars a bit.