Cat’s Eye nebula -NGC6543

The Cat’s Eye (NGC 6543) is a planetary nebula in the constellation Draco. Thanks to the Hubble Space Telescope, during the last years it was possible to determine the exact distance from the Earth, which is about 3600 light years.
The nebula was discovered on February 15, 1786 by William Herschel.
The relative brightness of the nebula is 8.1 mag. The cat’s eye has a very complex structure. The central star of the Cat Nebula is about 10,000 times brighter than our Sun! And its diameter is 0.65 times larger than that of our Sun.

Telescope ASA 10″ F/3.6 10N ASTROGRAPH OTA
Focal length 900 mm
Mount DDM 85
Imaging camera Atik 460EX mono
Guiding cameras  –
Guiding optics  –
Focal reducers ASA 3″ Wynne Corrector 0,85x
Constellations Draco
Distance 3600 light years
RA center 17h 58′ 32″
DEC center +66°37′ 47″
Location taken Slovakia
Date taken 07/2022
Pixel scale 1.04 arcsec/pixel
Filters Astronomik Ha 6nm ,
Astrodon OIII 5nm,
Astrodon RGB,
Exposure 60×600 s.  Ha filter,                                                                                      116x5s. Ha filter
76×600 s.  OIII filter                                                                                    153×120 s. L filter,                                                                                                    256x10s. L filter                                                                                                  68×120 s. R filter,                                                                                              224x10s. R filter
66×120 s. G filter,                                                                                                  100x10s. G filter
77×120 s. B filter,                                                                                                    166x10s. B filter
Total exposure cca.34,5 hours
Processing software PixInsight, CCD Inspector

The Cat’s Eye Nebula processing object (RGB-BICOLOR) was captured using Hydrogen-alpha H-α 6nm (656.3 nm), Oxygen OIII 5nm (500.7 nm) and RGB filters. This photo is one of the first where I use the DDM85 mount. The mount eliminates guiding at the star and increases the accuracy of astrophotography.