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NGC 6914 region OSC + duoband NBaccents

Posted: Tue Oct 15, 2024 3:01 pm
by dx_ron
Following the crowd... Using the AT65EDQ (420mm) + IMX571c, I decided to frame it to include the gamma-Cyg nebula and the Propeller in addition to NGC 6914. Probably not the most artistically compelling composition, with the 3 main subjects spread around the edges of the image, but I never did well in art class anyway.

About 5.5 hours OSC + 8.7 hours L_Ultimate duoband. Of course the duoband is almost all Ha. Processed the main (OSC) mage with Crop, Bin 50, Wipe, Optidev (16-bit), Contrast, a touch of Sharp only in the region right around the reflection nebulosity, SVD, Shrink (leaving out the larger stars with surrounding Ha, because they looked funny if shrunk), Color, NBa (pure red / teal), a touch of SS (0% strength) and a touch of NR (2 pixels).
NGC_6914_OSC+Lu_v2a_2560.jpg
NGC_6914_OSC+Lu_v2a_2560.jpg (496.4 KiB) Viewed 17656 times

Re: NGC 6914 region OSC + duoband NBaccents

Posted: Thu Oct 17, 2024 4:47 pm
by decay
dx_ron wrote: Tue Oct 15, 2024 3:01 pm Probably not the most artistically compelling composition, with the 3 main subjects spread around the edges of the image, but I never did well in art class anyway.
:lol: Indeed there seems to be some kind of a triangle visible in the nebula structures. And I wouldn't have thought that Gamma-Cygnus and the Propeller are so obvious brighter than the surrounding nebula clouds.
Probably not easy to process and to decide how to distribute the available dynamic range. You definitely succeeded with regard to the brighter parts (Gamma-Cyg and Propeller). I'm not 100% sure about the darker parts, maybe there's still some signal hidden?
dx_ron wrote: Tue Oct 15, 2024 3:01 pm a touch of SS (0% strength) and a touch of NR (2 pixels)
I never reduced strength so much. Interesting, I will give that a try. Great result with only conservative use of SuperStructure and NoiseReduction modules - probably you gathered a lot of signal. :thumbsup:

Best regards, Dietmar.

Re: NGC 6914 region OSC + duoband NBaccents

Posted: Thu Oct 17, 2024 9:32 pm
by dx_ron
decay wrote: Thu Oct 17, 2024 4:47 pm Probably not easy to process and to decide how to distribute the available dynamic range. You definitely succeeded with regard to the brighter parts (Gamma-Cyg and Propeller). I'm not 100% sure about the darker parts, maybe there's still some signal hidden?
I maybe could have made all of the background turn red, but I'm generally OK with leaving a bit on the table.
decay wrote: Thu Oct 17, 2024 4:47 pm
dx_ron wrote: Tue Oct 15, 2024 3:01 pm a touch of SS (0% strength) and a touch of NR (2 pixels)
I never reduced strength so much.
I bet not! I meant to type 60%! (or maybe 70%, can't remember exactly now). I find a low-strength SS gives a bit of noise reduction plus pushes the stars back just a bit, without the plastic feel of 100% SS.

Re: NGC 6914 region OSC + duoband NBaccents

Posted: Fri Oct 18, 2024 7:17 pm
by dx_ron
Another wrinkle in terms of the overall dynamic range is that the Ha is all coming via NBaccents. I'm never quite sure how what I set in the lead-in to that module is going to look in the composite. In addition, I did not use either HDR or Sharpen on the OSC base image, nor did I try going back to those modules after NBaccents. Maybe I'll play around with that someday when I have spare time.

As for the Propeller - yeah, it is quite bright. Shows up quite well in each incoming duoband sub in the simple screen stretch applied by the Ekos fits viewer.

I put it up on astrobin. Here's the link: https://astrob.in/vvn011/0/