1 stack of 100 60s images, Canon 800D at ISO 800, Canon 400mm f5.6 lens at f6.3, iOptron Skyguider Pro tracker. 100 darks, 120 biases. Processed in PixInsight as below

***** Integration

lightvortexastronomy tutorial (https://www.lightvortexastronomy.com/tutorial-pre-processing-calibrating-and-stacking-images-in-pixinsight.html)

* CC defect list + master dark (sigma = 8)

35*(1-(FWHM-FWHMMin)/(FWHMMax-FWHMMin))

+ 15*(1-(Eccentricity-EccentricityMin)/(EccentricityMax-EccentricityMin))

+ 20*(SNRWeight-SNRWeightMin)/(SNRWeightMax-SNRWeightMin)

+ 30

img 8611 ref

* ESD integration

* drizzle integration, gaussian kernel

*****Linear processing

*** Initial

* Crop

* DBE tolerance 3

* CanonBandingReduction

*** Color calibration

* Photometric CC with background upper limit 0.001 on a corner with no hydrogen clouds, FL 400 pixel 2 centered on Bubble nebula

* Background neutralization

* SNCR green, average neutral, preserve lightness, 0.5

*** Denoise

Using https://jonrista.com/the-astrophotographers-guide/pixinsights/effective-noise-reduction-part-2/ as implemented by EZSuite.

* TGV edge protection 1e-5, default MMT

***** Nonlinear

*** Initial stretch and denoising

* masked stretch, default settings

* ACDNR with mask, as per https://jonrista.com/the-astrophotographers-guide/pixinsights/effective-noise-reduction-part-3/ (extract luminance, histo stretch with mid to 50% - shadows 0.05 mids 0.07, blur 4 layers of a trous apply inverted) , chrominance amount 1 stdev 4 structure size 5

* extract luminance, histo stretch for mids to 50%, apply on image, denoise with default EZDenoise method. Then, histogram stretch the image (shadows 0.053 highlights 0.8 mids 0.42) and apply another layer of ACDNR

* fix sensor dust: split image in starless + stars, clonestamp out dust trail, add starless + stars back together

* EZDenoise, TGV 8e-3. default MMT

*** Star fixes

* with a starnet starmask on, increase star saturation with curves a lot

* ezstar reduction, morphological, 8 iterations

*** LHE

* create star_mask, extract luminance = star_mask_l

* kernel 512 contrast 1.5, blend star_mask_l * nova + (1 - star_mask_l) * (x * lhe + (1-x) * nova), x=0.67

* kernel 256 contrast 1.5. blend star_mask_l * nova + (1 - star_mask_l) * (x * lhe + (1-x) * nova), x=0.33

* create range mask lower limit 0.2 upper 0.78 fuzziness 0.72 smoothness 5.50. Increase saturation with curves.

* EZDenoise, TGV 8e-3. default MMT

*** Star fixes #2

* another ezstar reduction, morphological, 8 iterations

*** Background color blotch fix

* ACDNR on chrominance, stdev 4 iterations 3, with lightness mask mids 0.03 shadows 0.2

*** Sharpen

*MMT 6 layers, biases 0.05 0.05 0.025 0.025 0.012 0.005

*** Final resize

* Crop to 1.66 ratio

* Downsample 3x w/ integer resample