Decided to keep a lot of the green in this one compared to my previous SHO images. This is a false color image, and in true color this nebula is mostly red. I had originally shot this in Ha + Sii only last December, but couldn't really decide on a palette I liked, so I recently added on some Oiii. This target pretty much has no Oiii signal in it, except for some reflection nebula in the bright area, but I'm pleased with how it turned out with the addition of Oiii data. Captured over 3 nights from December 13th to January 22, 2022 from a Bortle 6 zone.
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**[Equipment:](https://i.imgur.com/6T8QNsv.jpg)**
* TPO 6" F/4 Imaging Newtonian
* Orion Sirius EQ-G
* ZWO ASI1600MM-Pro
* Skywatcher Quattro Coma Corrector
* ZWO EFW 8x1.25"/31mm
* Astronomik LRGB+CLS Filters- 31mm
* Astrodon 31mm Ha 5nm, Oiii 3nm, Sii 5nm
* Agena 50mm Deluxe Straight-Through Guide Scope
* ZWO ASI-290mc for guiding
* Moonlite Autofocuser
**Acquisition:** 15 hours 36 minutes (Camera at Unity Gain, -20°C)
* Ha- 68x360"
* Oiii- 23x360"
* Sii- 65x360"
* Darks- 30
* Flats- 30 per filter
**Capture Software:**
* Captured using [N.I.N.A.](https://nighttime-imaging.eu) and PHD2 for guiding and dithering.
**[PixInsight Processing:](https://www.youtube.com/watch?v=u7FuApFSGuA)**
* BatchPreProcessing
* SubframeSelector
* StarAlignment
* [Blink](https://youtu.be/sJeuWZNWImE?t=40)
* ImageIntegration
* DrizzleIntegration
**Linear:**
* DynamicCrop
* AutomaticBackgroundExtraction
* DynamicBackgroundExtraction
* EZ Decon/Denoise (Ha only)
* STF applied via HistogramTransformaion to bring each channel nonlinear
**Combining Channels:**
* PixelMath to make classic SHO to RGB image
**Nonlinear:**
* LRGBCombination with Ha as luminance
* Invert > SCNR > Invert > SCNR to remove magenentas and a *little* bit of green
* Shitloads of CurveTransformations to adjust lightness, contrast, saturation, hues, etc.
* LocalHistogramEqualization
> two rounds of this, one at size 16 kernel for the finer 'feathery' details, and one at 100 for larger structures
* Invert>SCNR>Invert with star mask to remove magentas from stars
* MLT Noise Reduction
* EZ Star reduction
* Extract L channel > LRGBC again for chrominance noise reduction
* More Curves
* Resample to 60%
* Annotation
lefty7283
