Probably should've gotten more exposure time on this, but it was already way out of season. Captured over several nights in January 2024, from a Bortle 9 zone
duplicated each image and removed stars via StarXterminator. Ran DBE with a shitload of points to generate background model. model subtracted from original pic using the following PixelMath (math courtesy of /u/jimmythechicken1)
$T * med(model) / model
**Narrowband Linear:
Blur and NoiseXTerminator
Duplicated the images before stretching to be used for separate stars-only processing
STF applied via histogramtransformation to stretch nonlinear
Stars Only Processing:
StarXTerminator to make stars only image form each channel
PixelMath to combine star images (SHO palette)
SpectroPhotometricColorCalibration (narrowband working mode)
SCNR Green
ArcsinhStretch + HT to stretch nonlinear - to be combined later with starless pic
Nonlinear:
PixelMath to combine stretched Ha, Oiii, and Sii images into color image (SHO palette)
Invert > SCNR > invert > SCNR to remove greens and magentas
Shitloads of Curve Transformations to adjust lightness, hues, contrast, saturation, etc
LRGBCombination with stretched Ha as luminance
more curves
NoiseXterminator
LocalHistrogramEqualization (at small and large scales to target varying structures)
MLT for large scale chrominance noise reduction
Extract L --> LRGBCombination for smaller scale chrominance noise reduction
Pixelmath to add in the stretched stars only image from earlier
This basically re-linearizes the two images, adds them together, and then stretches them back to before