Sh2-117 (OK, North America + Pelican). Two ways

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dx_ron
Posts: 288
Joined: Fri Apr 16, 2021 3:55 pm

Sh2-117 (OK, North America + Pelican). Two ways

Post by dx_ron »

Been cloudy here for quite a while, so I've had way too much time to fuss with these data.

AT65EDQ (420mm f/l) + Risingcam IMX571c
21 hours (5-minute subs) L-Ultimate duoband filter
2 hours (45s subs) OSC

"Bayer drizzle" registration instead of debayering in Siril, binned to 50% near the end of processing

Not two dramatically different renditions - the main difference is the RoI in Optidev.

A large horizontal RoI across both nebulae:
C20_Lu_Larger_mask+rgb.jpg
C20_Lu_Larger_mask+rgb.jpg (485.75 KiB) Viewed 3699 times
dropbox link to the .tiff (because I have not decided what to upload to astrobin yet): https://www.dropbox.com/scl/fi/dtn68u1o ... ch7pl&dl=0

Much smaller RoI focused on the Cygnus Wall region:
C20_Lu-only_wall_roi2_ss65_bin50_nr2_v2a+rgb.jpg
C20_Lu-only_wall_roi2_ss65_bin50_nr2_v2a+rgb.jpg (460.59 KiB) Viewed 3699 times
dropbox .tiff: https://www.dropbox.com/scl/fi/1ejw79t1 ... hqwrf&dl=0


Layering in the rgb stars was really fiddly, and I'm still not all that happy with the bright stars. I think I should re-think my automatic choice of 300s subs for the 3nm duoband filter.
Stefan B
Posts: 475
Joined: Sat Oct 31, 2020 8:59 pm

Re: Sh2-117 (OK, North America + Pelican). Two ways

Post by Stefan B »

Hi Ron,

both are detailed and deep renditions :thumbsup: I prefer the first version which appears softer and shows more of the faint stuff without losing details. It also appears a bit different with regard to contrast, especially in the OIII rich part of the North America Nebula. Maybe it's due to the different ROI but it could also be caused by different settings (or outcomes due to different input) in HDR. The second version has a bit of what Martin called the shattered glass look. Did you use HDR in your workflow.

The teal OIII is a matter of taste. It's not mine ;) But I know it's hard to change in ST's color module.

Did you try NBAccent? Would be interesting to know how that would look like.

Regards
Stefan
dx_ron
Posts: 288
Joined: Fri Apr 16, 2021 3:55 pm

Re: Sh2-117 (OK, North America + Pelican). Two ways

Post by dx_ron »

Thanks, Stefan!

No, I still haven't decided yet. I kind of like the more "dramatic" look with the less aggressive initial stretch, but I also appreciate wanting to "bring out" all the nebulosity. I did use HDR on both, but toned down. Highlights all the way down to 1.08, and dark/light enhance down to the mid-20s. Also some toned-down (~200%) Sharp, with the two smallest scales zeroed out. I tried once with NB accents. But with only a couple of hours of OSC it was really lacking.

Next time I'm frozen out of new imaging by moon and/or clouds, I will have another go at it.
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