I totally didn't procrastinate processing this thing, and it's just pure coincidence that I finally took a stab at it in October...

In hindsight, this really could've used another night of data (particularly the L), but I only had one clear night at the dark site. I was just happy to get out of the light pollution and shoot a dark nebula for once! Captured on August 17th, 2025 from a bortle 3 zone (deerlick astronomy village).

Places where I host my other images:

Flickr | Pixelfed

Equipment:

• 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: 7 hours 21 minutes (Camera at -15°C), half unity gain

• L - 56x180"

• R - 30x180"

• G - 30x180"

• B - 31x180"

• Darks- 30

• Flats- 30 per filter

Capture Software:

• Captured using N.I.N.A. and PHD2 for guiding and dithering.

PixInsight Preprocessing:

• BatchPreProcessing

• StarAlignment

• Blink

• ImageIntegration per channel

• DrizzleIntegration (2x, Var β=1.5)

For the L channel I did 3 stacks each with 1/3rd of the data, then combined them to an RGB image (was still grayscale) to use deepSNR noise reduction. after this it was properly converted to mono

• Dynamic Crop

• MultiscaleGradientCorrection

  First time trying out the MARS thing in pixinsight. It seems to work very well

Luminance Linear:

• BlurXterminator

• Stars removed with starx

• ArcsinhStretch + HistogramTransformation to stretch nonlinear

RGB Linear:

• ChannelCombination to combine monochrome R G and B images in to single color image

• MultiscaleGradient Correction

• SpectrophotometricColorCalibration

• BlurXterminator (correct stars only)

• HSV Repair

• Extracted stars with starXterminator, to be used later for independent starless processing

• ArcsinhStretch + HistogramTransformation to stretch nonlinear

• Slight saturation curve boost

** Stars only processing:**

• ArcsinhStretch + HistogramTransformation to stretch nonlinear

• Slight SCNR to remove greens and magentas

• Curves to boost saturation

Nonlinear Processing:

• LRGBCombination to combine stretched RGB and L images

• DeepSNR Noise reduction

• Several rounds of curve adjustments for lightness, contrast, saturation, color balance, with various masks

• LocalHistogramEqualization

• More curves

• Pixelmath to add in the stretched RGB stars only image from earlier

  This basically re-linearizes the two images, adds them together, and then stretches them back to before. More info on it here)

  mtf(.005,

  mtf(.995,Stars)+

  mtf(.995,Starless))

• BlurX to sharpen the stars a little

• Even more curves

• Slight SCNR

• Resample to 70%

• Tighter crop in on just the nebula

• Annotation