I decided to do a deep dive into just the core of the Heart Nebula itself. Mellotte 15 is the name for the bright structure in the image, but the rest of the nebula itself is pretty extensive, and features the nearby soul nebula. IMO the uncropped heart nebula looks more like a chode with huge balls, but I can kinda see where it got it’s heart name… Captured over 8 nights in November 2024 from a bortle 9 zone.

Places where I host my other images:

Flickr | Instagram

---

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: 29 hours 50 minutes (Camera at -15°C), unity gain

• Ha - 58x600"

• Oiii - 62x600"

• Sii - 59x600"

• 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)

• Dynamic Crop

• DynamicBackgroundExtraction

  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

• made SHO image and extracted stars to be processed separately

• StarXterminator to completely remove stars from each Ha, Oiii, and Sii image

• HistogramTransformation to stretch nonlinear

Stars only image:

• SpectrophotometricColorCalibration (narrowband working mode)

• HSV repair

• arcsinhstretch

• scnr > invert > scnr > invert to remove greens and magentas

• HistogramTransformation

• (combined with starless pic later on)

Nonlinear:

• PixelMath to combine monochrome Ha Oiii and Sii images into a color image with SHO --> RGB, respectively

• HistogramTransformation to adjust red green and blue color channels separately (basically stretched R and B, and toned the G down some)

• LRGBCombination using stretched Ha as luminance

• DeepSNR

• Shitloads of Curve Transformations to adjust lightness, hues, contrast, saturation, etc

• Clone stamp to remove one weird small blue speck near the core of the nebula (might’ve just clipped the colors a little too much in the histogram adjustments above^)

• LocalHistogramEqualization (two rounds of this. one at kernel radius 16 for small scale detail, and one at 500 for large structures)

• More curves

• DarkStructureEnhance script (0.15 amount)

• 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))

• some more curves

• One more round of noiseX for small scale noise reduction

• DynamicCrop in on just the core region

• Resample to 80%

• Annotation