IC1848, The Soul Nebula

30 September, 2023
mono narrowband nebula

Acquisition Details

Frames 102 60 164
Palette Red Green Blue
Exp. Time 180s 180s 180s

Final Masters

Sulfur (SII)
Hydrogen (Hα)
Oxygen (OIII)


This is the Soul Nebula or 👻 IC1848 👻. This image is a compilation of three narrowband channels (7nm): Sulfur-2, Hydrogen-alpha and Oxygen-3.

It is shot over five nights during full moon. The refraction of moonlight causes more background noise to be visible, even with an integration time of about 16.5 hours!

By assigning each of the three narrowband channels to a color (RGB) it allowed me to recreate that iconic Hubble palette.

Astrometry Calibration

Astrometry Job 8523967
Center (RA, Dec) (43.865, 60.472)
Center (RA, hms) 02h 55m 27.528s
Center (Dec, dms) +60° 28’ 18.197”
Size 2.41 x 2.53 deg
Radius 1.750 deg
Pixel Scale 1.56 arcsec/pixel

Data Processing

Processing was done in PixInsight only. Steps of the process are listed below:

  1. DynamicBackgroundExtraction on separate channels,
  2. SPCC,
  3. Color Calibration for evening the SHO levels,
  4. DarkStructureEnhance,
  5. StarXTerminator (splitting stars and background),
  6. BlurXTerminator on seperate stars and starless image,
  7. HistogramTransformation, a.k.a. stretching
  8. Masking and denoising applied to background layer using NoiseXTerminator,
  9. Boosting and adjusting colors and saturation using CurvesTransformation,
  10. PixelMath for merging the stars image back,
  11. Final color adjustments
  12. Star reduction/resizing using BlurXTerminator (stellar only)