English: The gamma cas nebula gets its name from the bright star gamma cassiopeiae (aka Navi) observed in the bottom right quadrant in the image. It is part of the well-known W-shaped asterism in the Cassiopeia constellation and located 550 years from earth.

The singular nebula actually consists of two distinctive emission nebulae, IC59/Sh2-185 (center and right) and IC63 (lower left). They are strikingly illuminated by the bright blue star which is 34,000 times more luminous and has 17 times our Sun's mass. The 1.5-3 magnitude star's energy, caused by its extremely rapid rotation rate that distorts its appearance, is also responsible for pushing and dispersing the emissions of these nebulae into the interstellar medium even though they are located light years apart.

This series of images were taken without my FC35 reducer, going from the normal f/4.9 to f/7.4. As a result, there is a large number of stars captured which I had to repeatedly reduce the size of to make it less busy. The series (https://www.astrobin.com/nouak1) contains a Ha-only image (A); PixInsight-only processing with (B) and without (C) star reduction, TopazStudio 2 processing with increasing blue tone without star reduction (D) and with (E-H). There's also one with more traditional colours (J).

There is some reflection signal in here that I hope to come back to without narrowband filters and will try to overlay all the channels. I chose to use pale colours rather than the traditional bright golden-blue Hubble palette since there was a strong overlap of the Ha and S2 signals, overwhelming the O3, and I also wanted to choose a processing style that fit the "ghost nebula" monicker this nebula is known by.