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Posts Tagged ‘horsehead nebula’

Barnard’s Loop

March 7, 2016 1 comment

When I was a kid, Barnard’s Loop was something that I saw on star charts, but it seemed so hopelessly dim, I never expected to actually see it.  And even when I started CCD imaging, it was still a somewhat elusive object: too large to capture unless you used a wide-angle lens, and even then you wouldn’t get decent resolution.  But the combination of a full-frame sensor and a very fast telephoto lens turns out to frame it nicely.

This image obviously has more in it than Barnard’s Loop.  M42/43, the Flame Nebula, the Horsehead Nebula, and M78 all sit nestled within the Loop.  But more interestingly for me, you can start to see the overall Orion Molecular Cloud complex in there: all the dim tendrils that connect each of these objects, some glowing, some blocking the view of the glow.  I regret stopping the lens down to f/2.8 now, as perhaps I would have captured more of the overall cloud that way.  I’d go back and retake the shot if I weren’t having so much fun with this new lens on other targets (and if I hadn’t spent five hours processing this one).  But I’ll consider this a success, as it’s another childhood dream accomplished.

Barnards_Loop_FINAL_50 percent

(This image is reduced to 25% of full size, as the 6D’s output is over 20 megapixels.)

Image data:

  • Exposures: 81×2 min at ISO800 – total exposure time:  2h 42m
  • Telescope: Samyang 135 mm f/2 lens at f/2.8 (reviewed here)
  • Camera: Canon 6D (modified) with Astronomik CLS clip-in filter
  • Mount: Takahashi EM200
  • Guiding: Orion Starshoot, guided using PHD2
  • Conditions:  fair transparency, calm winds
  • Processing: DeepSkyStacker -> PixInsight -> Photoshop
  • Date: Feb 28, 2016

 

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The Horsehead Nebula in H-alpha

February 27, 2012 Leave a comment

The 1983 National Geographic cover featuring this nebula really captured my imagination as a child.  I’ve always thought it was one of the coolest things in the sky, and it’s amazing that amateurs can now take images from their backyard that rival the best professional observatory pictures then.

This grayscale image represents 27 ten-minute exposures through a Hydrogen-alpha narrowband filter. This filter captures only deep-red light produced by ionized Hydrogen (and Nitrogen) in the nebula.  Consider that the visible light we see ranges from about 400 to 700 nm in wavelength.  Here, you are only seeing the light from a tiny sliver of the spectrum from 653-659 nm which, fortunately for us, is where nearly all of the light from this object is emitted.

The Horsehead Nebula in H-alpha

Image data:

Exposures:  27 x 600s Ha, a total of 4h 30m, taken 17 Feb 2012.

Software:  guiding by PHD, stacking in DeepSkyStacker, processing in Photoshop CS3

Telescope:  Borg 77EDII w/ f/4.3 reducer

Camera:  SBIG ST-8300M with Baader filters

Mount:  CGEM

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