NGC6543: NGC6543, also known as the Cat's Eye Nebula, is a tiny, bright (magnitude 9) planetary nebula, the type of nebula which it is generally thought our Sun will produce as nuclear fusion slows and then dies in its core, and it expels its outer layers of gas. Estimates of its distance from Earth vary, but tend to be around 3000 light years. The amorphous blob to the right of the nebula is actually a part of the outer envelope of the nebula, but with its own catalog designation, IC4677.

Technical Information:

LRGB: 152:56:56:91 (Luminance consisted of eight minute images; R&G consisted of eight minute images, B consisted of 13 minute images, all unbinned).

Equipment: Meade 10" LX200 at f/12 (image resized up 50%, so equivalent to f/18), an SBIG ST-8XE camera/CFW-8 color filter wheel, guided by an SBIG AO-7 adaptive optics device, guiding at about 7 Hz (luminance) and 1-3 Hz (RGB).

Image Acquisition/Camera Control: CCDSoft V5.

Processing: All images calibrated (darks, dawn flats and flat-darks) and registered in AIP4WIN. All layers average combined in Ray Gralak's sigma reject program. Five iterations of Lucy-Richardson deconvolution routine applied using CCDSharp. Color combine, very gentle unsharp mask on the luminance layer, and adjustment of curves and levels, performed in Photoshop 6.0. The extreme range of brightness in the nebula, ranging from a mag 10 star at the center to the extremely dim outer gas of the nebula, made processing tricky, and my decision to include IC4677 (which otherwise would have disappeared in my effort to avoid burning out the nebula) further complicated things. I ended up processing the image several times, and picking the pieces from each I liked, and layering them together in Photoshop.

Location: All images taken in my yard in Redmond, WA, USA, elevation 500'.

Date: Luminance images taken on the night of June 2, 2003; RGB taken on the night of June 3, 2003.

CCD Temperature: -25C

Moon Phase: Waxing crescent

Seeing: 2.3 Arcsecond typical FWHM in single calibrated image.

Copyright 2003 Mark de Regt