I started this project at the request of Tim Schaeffer
@Tim Schaeffer to image the tiny subject PWN with much higher resolution using the CDK24. You can see his original image with Palmito at
https://www.astrobin.com/zzoau6/.
Both myself and William Ostling
@William Ostling processed the channel images output from Pixinsight's WeightedBatchPreprocessing.
My goal was to replicate what you might see using RGB but with HaSIIOIII filters. You can see the comparison here with just 1.5 hours of RGB vs nearly 24 hours of HaSIIOIII. The HaSIIOIII version does not use an RGB overlay...
I kept the processing relatively simple to help minimize artifacts...
1. BlurX, Stretch, Levels, Curves, LHE and NoiseX on each Ha, SII, OIII. The same level and curve on each channel.
2. Combined in Photoshop for natural color using Screen layers similar to what Don Goldman describes in the book "Lessons from the Masters" under chapter "Narrowband Imaging".
3. Combined imaged followed by HVLG, color balance shadows, Selective Color Enhancement on Reds and Whites, NoiseX, mild USM on PWN and mild curve stretching.
4. Mild single-pass Star Shrink using 9, 8, -3.
5. Screen a more heavily stretched starless Ha, SII and OIII over the top.
William’s goal is to reveal the nebulosity in a more colorful SHO palette. The different colors clearly show the composition of the nebulosity within the PWN as well as that of the SNR surrounding the PWN.
William sought to preserve the detail within the nebula as much as possible, as that was after all the main goal of this project. (-:
I'd also like to point out the amazing depth of this image. Feel free to zoom into the surrounding nebulosity to see the fine filaments making up this wonderful region.
Thanks for looking!
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