AstroBinAstroBin
Celestial hemisphere:  Northern  ·  Constellation: Draco (Dra)  ·  Contains:  Cat's Eye Nebula  ·  IC 4677  ·  NGC 6543  ·  NGC 6552  ·  PK096+29.1

Image of the day 06/24/2014

    NGC 6543 - Cat's Eye Nebula, Colin McGill
    Powered byPixInsight

    NGC 6543 - Cat's Eye Nebula

    Image of the day 06/24/2014

      NGC 6543 - Cat's Eye Nebula, Colin McGill
      Powered byPixInsight

      NGC 6543 - Cat's Eye Nebula

      Equipment

      Loading...

      Acquisition details

      Loading...

      Description

      The Cat's Eye Nebula was discovered by Herschel in the late 18th century. It was the first planetary nebula to have its spectrum measured, which demonstrated that it was largely composed of hot gases. Previously, this was thought to be composed of stars.

      I took this over two nights from Nerpio. The first night was exceptionally good seeing (1.5-2.0"), but I mucked up my CCDcommander file and forgot to take any luminance data. Fortunately, I took all my RGB frames at 1x1 binning, and combined the best frames from this night, and the best luminance frames from the second night, to create a psuedo luminance. The High SNR in the core of the nebula permits strong deconvolution, which brings out the structure in the core - not quite at Hubble level, but pretty good! The outer layers of the nebula are also shown well - with the strong contrast between the core and the outer layers, this is not an easy object to process.

      I also really like the barred spiral galaxy, NGC 6552 just to the left of the nebula.

      I will also post a cropped version to show the detail in the core more easily.

      Looking again at this in a darkened room, I realised I had left too much noisy background. I created a new luminance mask by moving the blackpoint to set the background to zero, then bosted the luminance of the remainder to make the mask have a high value elsewhere. I then used the inverse of this mask to smooth the background, reset the blackpoint, and finally a histogram transform to dim the background. Makes it look much cleaner.

      Comments

      Revisions

      • Final
        NGC 6543 - Cat's Eye Nebula, Colin McGill
        Original
        NGC 6543 - Cat's Eye Nebula, Colin McGill
        D
        NGC 6543 - Cat's Eye Nebula, Colin McGill
        E
        NGC 6543 - Cat's Eye Nebula, Colin McGill
        F

      Sky plot

      Sky plot

      Histogram

      NGC 6543 - Cat's Eye Nebula, Colin McGill
      ×

      Warning!

      This operation will reload the current page. If you have any unsaved information in a form, it will be lost.

      You can also dismiss this window, and your operation will be applied at the next page navigation.