Sunday, August 15, 2010

The Witches Broom

Click on image for a larger view
Just got back from one hell of a hot camping trip.  I spent eight days in 100 degree weather with a few amateur astronomer friends at the Astronomical Society of Kansas City's Dark Sky Site (near Butler, MO).  Thankfully, night time temperatures were in the 70's and night time is why I was there.  Six out of those eight nights were clear and therefore I got a chance to image several deep sky objects with my telescope.  The image above is one of those objects.

The Veil Nebula image is only part of a much larger complex of nebulosity also known as the Cygnus Loop.  This part is on the west side of the "loop", so it is also called the "Western Veil".  A much more descriptive name is the "Witches Broom".   It's true identity, however, is the leftover remnants of a supernova explosion. some 5000 to 8000 years ago.  The remnants have since expanded to a circular area some 3 degrees in diameter.  An area this big would fit 6 full moons across.  Even though it covers an area so big in the sky, it is rather faint and requires optical aid to see it.  The bigger the telescope, the brighter it gets.  Even getting images of this object is not easy.  I haven't been happy with previous images, but this time using my 7.5" Mak-Newt telescope, I took 10 images, each image 15 minutes long, for a total of 2.5 hours combined, calibrated those images with "Bias, Flat and Dark" images, then spent a few hours bringing out the details with Photoshop.  Not a simple "click", but hours of work for one image.

Technical Details:
* Telescope: 190mm (7.5") Orion Maksutov-Newtonian
* Focal Length: 1007mm
* Focal Ratio: f/5.3
* Mount: Celestron CGE
* Exposures:
> 10 Lights, 15 minutes long
> 20 Biases
> 20 Flats
> 1 Dark
* Calibration: Removed bad pixels on Lights using the single Dark with "Nebulosity" software
* Processing: Aligned and Stacked using "DeepskyStacker" software
* Finished: Photoshop CS3


  1. Wow Tom, When I read about the 3 hour's to get the picture...I spend a couple of hours every night on our family pics so I do appreciate your hard work and your expert astro pictures and your dedication to your hobby...You are a inspiration to lots of folks...Tony K

  2. Thanks Tony. Yes, astrophotos do take a lot of time and patience. Having done this myself only makes me appreciate more what other astrophotographers go through to get their pictures.