The Horsehead nebula (B33) is a dark nebula in Orion. The Flame nebula, also called the Christmas Tree nebula (NGC 2024) is an emission nebula. NGC 2023 lies between the Flame and the Horsehead and is a reflection and emission nebula. Alnitak is the bright star that dominates the upper left hand corner of the image.
This project started as an Alnitak torture test. I recently upgraded from an ASI1600MM Pro to an ASI294MM Pro. I stuck with approximately the same sensor size as I am not yet ready to upgrade my filter wheel and filters. I primarily upgraded for the increase in sensitivity and dynamic range. But the 1600 also has a problem with very bright stars. It produces a microlensing artifact that I personal don't like (you can see this artifact in my image of the Pleiades:
https://www.astrobin.com/full/aanrzj/0/). As a result, I haven't imaged the Horsehead nebula since I acquired the 1600.
I started this project in narrowband but as I was finishing that data, conditions were holding up and I was able to get some really nice RGB data. In the end I liked the RGB data much better than the narrowband data and only used the Ha image to enhance my synthetic luminance image. The signal in this data was so strong that the only noise reduction I performed was Mure Denoise after stacking my initial subs. I felt no other noise reduction was necessary.
Acquisition Details:
Dates 12/06/2020, 12/14/2020 - 12/16/2020
Gain 120, temp -20C
Red: 170 x 60 sec
Green: 170 x 60 sec
Blue: 164 x 60 sec
Gain 200, temp -20C
Ha: 50 x 300 sec
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