The Pelican Nebula
Astrophotography
The Pelican Nebula (IC5070, 1,800 light years from Earth) in the constellation Cygnus, in the middle of the Milky Way. Captured over 2 nights of fantastic seeing conditions in August, 2021.
After shooting a wider shot that included both the North American Nebula and the Pelican Nebula, I wanted to focus on the Pelican Nebula. I recomposed the telescope so the Pelican Nebula would be in the middle of the frame and made sure to shoot with dithering enabled. In post, I drizzled 2x, which made the integrated images absolutely enormous–around 240 megapixels. Processing in PixInsight involved kicking off operations and then walking away from my computer for at least an hour at a time–and this is on an overclocked 18-core computer with a RTX3090 GPU (!).
Stacked in Astro Pixel Processor and edited in PixInsight. Shot in San Mateo, California, in Bortle 5/6 skies, August 29 and 30, 2021.
Subs
SII: 29 x 600 sec
H-alpha: 29 x 600 sec
OIII: 31 x 600 sec
Gear
Explore Scientific ED102-FCD100 / ES 3″ Field Flattener & 0.7x Reducer / EQR6-Pro / ASI6200MM Pro / Optolong filters / Orion 50mm & ASI120MM-S guide
Stacked in Astro Pixel Processor and edited in PixInsight. Shot in San Mateo, California, in Bortle 5/6 skies, August 29 and 30, 2021.
Workflow
- Stack in AstroPixelProcessor (lights, flats, darks, flat darks), drizled x2.0
- Denoise each channel
- Deconvolution on each channel
- Coarse HistogramTransformation / CurvesTransformation on each channel
- Star reduction on each channel
- PixelMath Combination using @thecoldestnights / Foraxx SHO
- R = (Oiii^~Oiii)*Sii + ~(Oiii^~Oiii)*Ha
- G = ((Oiii*Ha)^~(Oiii*Ha))*Ha + ~((Oiii*Ha)^~(Oiii*Ha))*Oiii
- B = Oiii
- CurvesTransformation
- Export to TIFF
- Crop and touch up in Lightroom (mild)