Messier 78 Casper the Friendly Ghost

Messier 78 Casper the Friendly GhostClick here for an annotated version of this target.

Messier 78 or NGC 2068, also known as Casper the Friendly Ghost (not sure how it applies, I don’t see a ghost), is a bright blue reflection nebula in Orion. The nebula can be found between Betelgeuse and closer towards Alnitak.

Messier 78 is the brightest reflection nebula among a group of nebulae, including NGC 2064, NGC 2067, and NGC 2071. These are part of the Orion B molecular cloud complex, including the Horsehead Nebula, the Flame Nebula, Barnard’s Loop, and M42, the Orion Nebula.

M78 can be resolved in binoculars and small telescopes. M78 has often been mistaken for a comet, which explains why the Comet Hunter Charles Messier cataloged this in his list of non-comets.

M78 was discovered in 1780 by Pierre Mechain and cataloged by Charles Messier shortly after.

M78 lies about 1350 light-years away at a magnitude of 8.3.

This was my first multi-night image, and I had acquired about 16 hours of data over three nights. It was a bit nerve-wracking to set up and preserve the camera rotation over multiple nights as I had to break down and set up each night. If I had a more permanent setup, I might have even gone for a few more hours.

Messier 78 Casper the Friendly Ghost This is why more data is always good. Left we have 40 x 300 seconds, right we have 169 x 300 seconds.
Noise reduction is the biggest advantage of more data.

Processing Info

I took 190 frames at 300 seconds each. Between clouds and haze, I threw away 31 frames. Having so much data allowed me to be selective, and I could throw out frames with high FWHM and eccentricities that I didn’t like. I stacked the 169 remaining frames along with 50 dark frames and 25 flat and dark flat frames.

The following processes were performed in PixInsight:

  • Channel Extraction
  • Linear Fit
  • Channel Combination
  • Dynamic Crop
  • Dynamic Background Extraction
  • Automatic Background Extraction
  • Background Neutralization
  • Photometric Color Calibration
  • EZ Decon
  • EZ Denoise
  • Histogram Transformation
  • LRGB Combination
  • Curves Transformation (X2 with a range mask. Inverted mask for the background and then non inverted for the target)
  • Color Saturation (X2 with a range mask. Inverted mask for the background and then non inverted for the target)
  • SCNR (Removed Green)
  • EZ Star Reduction
  • Local Histogram Equalization (Performed with a range mask)

Once I found what I liked, I saved the files and went to Photoshop. I played around with the levels, vibrance, and saturation a bit. I then ran Topaz AI DeNoise. I honestly didn’t need to be that aggressive with the noise reduction, as having 14 hours of data helped reduce noise.

With this target, I made a time-lapse of the stacking and processing flow.

The area of the sky in OrionHere you can see the area of the sky in Orion imaged.

Acquisition Data

  • Telescope: Explore Scientific ED127 f7.5 Air-Spaced Triplet Apochromatic Refractor
  • Camera: ZWO ASI2600MC Pro
  • Guide Scope: Orion ST80
  • Guide Camera: ZWO ASI290MM Mini. Dithering every image at 1 pixel each time.
  • Mount: iOptron CEM60
  • Software: NINA for image acquisition. PixInsight used for stacking and editing. Imported to Photoshop for final touchup and watermarking.
  • Other Accessories: AstroZap Dew Heater, Starizona Apex ED 0.65x L
    Reducer/Flattener, MoonLite CFL 2.5″ Focuser, High Res Stepper Motor, V3 Controller, Pegasus Astro Power Box Advance
  • Filters: Optolong L-Pro 2″
  • Exposure Time: 14 hour 5 minutes (169 x 300 seconds) -20°C
  • Date: November 16, 17, 18, 2020
  • Exposure Start: 22:34, 23:44, 22:59
  • Location: Voorhees State Park, NJ, United States
  • GPS Coordinates: Lat. 40.68187, Long. -74.89797
  • Temperature: 29°F/-2°C
  • Bortle Dark-Sky Scale: 4
  • job: 4039451
  • Avg. Moon age: 2.58 Days
  • Avg. Moon phase: 8.15%
  • RA center: 5h 46′ 49″
  • DEC center: +0° 4′ 26″
  • Orientation: 109.184 degrees
  • Field radius: 1.202 degrees
  • Magnitude: 8.3
  • Resolution: 3720 x 2330