Alright, finally. I have struggled with this target for years, stymied by the fact that it is unusually bright yet unusually difficult to process.
Last year I figured I'd gotten as far as I could with my conditions and equipment, but I thought I'd have another crack at it this year and add some Ha as well. I'm glad I did.
After some
helpful feedback in the forum, I realized that while I was now guiding and using a good broadband light pollution filter, a lot of the subs in the 2022 image were still from 2021 before I was guiding or using a filter. Furthermore, upon analyzing 2022's data, I discovered that an entire night was full of stars with a MUCH higher FWHM than any other night. So, I tossed most of the 2021 subs, and all 2022 & 2023 subs with FWHM > 3 (as determined by Astro Pixel Processor).
My Ha data, despite being 12 hours, was relatively poor. Continuum subtraction was extremely challenging, and I tried several approaches before finally finding one that worked (
thanks Steve!) and even then, I needed to mask out the core entirely.
The big surprise during processing was just how good the blue channel was in terms of contrast. I ended up extracting the blue channel and recombining the RGB image using blue as luminance. BIG improvement in detail.
As always, this one's for Bob. Happy early birthday!
Update: I added a revision with some sharpening added (USM and MLT, thanks Visible Dark!) and with a slightly less gauzy feel to the stretch. Please let me know which version you prefer!
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