NGC 6543 LRGB

NGC 6543 LRGB
5

NGC 6543 LRGB

L: 16 x 300s, R: 22 x 300s,
G: 16 x 300s, B: 15 x300s.
SPECIFICATIONS
Telescope ..........................................................................................................................................................................................................................
Telescope
SPA-2
Camera ..........................................................................................................................................................................................................................
Camera
QHY600M
Location ..........................................................................................................................................................................................................................
Location
IC Astronomy, Oria, Spain
Date of observation ..........................................................................................................................................................................................................................
Date of observation
11th - 17th August 2023
Filters ..........................................................................................................................................................................................................................
Filters
Astrodon LRGB
Processing ..........................................................................................................................................................................................................................
Processing
Astro Pixel Processor, PixInsight, Blur Xterminator, Star Xterminator, Noise Xterminator, GraXpert,Affinity Photo.
Credits ..........................................................................................................................................................................................................................
Credits
Nik Szymanek / Telescope Live
Start now your 1-week free trial to observe the night skies as you never did before
Try it free
See all photo
Comments

Hi Phil.
Yes, this was a bit tricky.
Whenever I process galaxies, planetary nebs etc. I always try to recover detail in the cores. Quite often, getting the galaxy right ends up blowing out the core (M31, M83 etc).
One way around this problem is to return to the RGB FITS file and rescale it in a way that shows detail in the core…the rest of the image doesn’t matter. I then overlay the original on top of the rescaled version and blend the two together. It takes a bit of practice but usually works well.
The NGC 6543 image was a bit more awkward as rescaling the RGB file didn’t work too well but improved the original image so I saved it and used it with the step outlined below.
I revisited the three individual RGB FITS images and noted that the red frame suffered the least from overexposure. I scaled this again in a way that just about recovered some of the core detail and blended that in with the luminance frame. Then I used the modified RGB image for the colour in the usual LRGB way.
It’s not ideal but is a lot better than the dreaded core blob without this method!
Hope this helps.
Regards,
Nik

Reply: 2