Urban M106

Here is an urban shot that has much more effort invested in the processing than the image capture. With the evenings getting shorter I'll have to start shooting the same target over multiple nights to get the kind of exposure needed to bring the faint detail out from my light polluted urban skies. Due to the shorter exposure and insufficient dithering, there were light pollution bands and blotches throughout the shot. Fortunately Images Plus has a great band removal that works well on these types of issues.

M106 is a spiral galaxy in Canes Venatici, near the Big Dipper, and because of its relatively large size exhibits rather low surface brightness, making it a difficult target for the urban imager. According to Wikipedia - Messier 106 (also known as NGC 4258) is an intermediate spiral galaxy in the constellation Canes Venatici. It was discovered by Pierre Méchain in 1781. M106 is at a distance of about 22 to 25 million light-years away from Earth. M106 contains an active nucleus classified as a Type 2 Seyfert, and the presence of a central supermassive black hole has been demonstrated from radio-wavelength observations of the rotation of a disk of molecular gas orbiting within the inner light-year around the black hole.

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Here is a very simple processing of a two hour subset of the same data to show the light pollution banding that was removed using the Images Plus band removal tool. This tool is a little tricky to use and its simplest application tends to leave dark bands radiating from bright things in the image or a gradient across the image that is brighter in the middle and darker at the edges. There is a simple, but tedious method to get around both of these artifacts and the above image shows results.
Object M106 RA 12:19.0 Dec +47:18
Date 5 April,2022 
Exposure 4 hours (24 X 10 minutes)
Conditions Bright urban Bortle 7 skies with a 20% illuminated  Moon in the sky for the first two hours of data, bright Bortle 7 skies with no Moon for the second two hours.
Gain 100
Camera Zwo ASI2600MC-Pro
Optics Prime focus of a  SkyWatcher Esprit 120 f/7 APO refractor with a focal length of 840 mm
Filter None
Location Bedford, St. Croix, Nova Scotia
Processing This image was captured using Sequence Generator Pro. Split star processed similar to this.