NGC6543 - Cat's Eye Nebula -

NGC6543 (Cat's Eye Nebula)

This image is a combination of two SPA-2-CMOS datasets from the Telescope Live archive: an LRGB(Ha) dataset and an HSO dataset. Inspection of the individual FITS files revealed that the H-alpha data are identical in both sets, which suggested that a combined processing approach would be the most sensible solution. This is particularly rewarding for the Cat's Eye Nebula, whose structure is strongly dominated by oxygen emission.

Although the raw data are generally of very high quality, seven H-alpha subframes were rejected due to quality issues. Some noise and artifacts were also present, especially in the SII data, while several channels showed noticeable gradients. For this reason, RGB data were primarily used for the stars and background field, while the nebula itself was enhanced using the narrowband H-alpha and OIII data.

The final image represents a total integration time of 18 hours 13 minutes after rejection of poor-quality frames.

Stacking was performed in Astro Pixel Processor (APP), processing in PixInsight, and ASIStudio was used for inspection and evaluation of the individual FITS files.

The combination of broadband RGB data and narrowband oxygen emission proved particularly effective in revealing the intricate shell structure of this remarkable planetary nebula.