About image NGC 6543, also called "Cat's Eye Nebula", is a planetary nebula visible in the constellation of the Dragon. It has an apparent magnitude of 9.8 and a high surface brightness, although its apparent dimensions are rather small (20 "the core and about 6' the halo). It is located at a distance of 3300 light years and is structurally one of the most complex nebulae currently known. The image was obtained from my home terrace in conditions of strong light pollution due to sodium lamps of public lighting (value sqm: 18.67 at the zenith). This result was achieved thanks to the use of narrow band interference filters and a long exposure divided over four nights.
Technical data Optic Celestron C9.25 Edge HD f/10 Mount Losmandy G11 with Ovision worm and FS2 Camera Atik 4000 with Starlight Xpress filter wheel 5 positions Filters Baader Ha 7nm and OIII 8.5nm, 50.8 unmounted Guiding system OAG LB Astro Proxima and Lodestar Exposure details Ha 24x20" + 22x900" bin1 -10C OIII 60x5" + 12x900" bin1 -15C + 9x900" bin1 -10C Total integration 11h Acquisition Maxim, PHD2 Processing Maxim, Photoshop CS5 SQM-L 18.67 Location Home terrace (Rescaldina, Italy) Date 8/9 June, 5/15 July 2014