This is my view of the Cat's Eye Nebula (NGC 6543) - a planetary nebula. The name comes from initial observations with early telescopes before it was understood what these are. This is a classic planetary nebula which is brief phase in the life of a sun-like star at the end of its red giant phase - as it expels outer layers of gas. This nebula's dying central star may have produced the simple, outer pattern of dusty concentric shells by shrugging off outer layers in a series of regular convulsions. The structure of the bright portion of the nebula is primarily caused by the interaction of a fast stellar wind being emitted by the central star with the visible material ejected during the formation of the nebula. The stellar wind, blowing with the velocity as high as 1900 km/s, has 'hollowed out' the inner bubble of the nebula, and appears to have burst the bubble at both ends. cite: <
https://en.wikipedia.org/wiki/Cat%27s_Eye_Nebula> <
https://science.nasa.gov/cats-eye-nebula-hubble>
The seeing near me has been bad - I have found that using bin 2x2 to match my imaging resolution to something closer to my guiding RMS seems to keep the image quality the same, more signal, and much smaller files (and processing time) to deal with.
The core of the planetary nebula is so bright, the linear version of the file before stretching shows impressive structure even before stretching - as seen in the image revision
For processing, the core is so bright, I used a combination of gradient masks during the stretching process (using Generalized Hyperbolic Stretching) to try to keep the detail in the core and surrounding nebula.
Short technicalTelescope: Celestron EdgeHD 9.25 SCT (FL 2350 mm, f/10)
ZWO ASI 2600mm (bin 2x2)
LRGB + Ha + OIII
Total exposure time: 9h 51min
The gear interface is evolving, so I will just manually type it here
43x200s OIII 6 nm
39x200s Ha 6 nm
37x100s L
24x100s R
24x100s G
24x100s B
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