NGC7293 - The Eye in the Sky

[Dave882]

Yes another Helix nebula! This time giving the big ol' stink eye up close at 2700mm and only just squeezing it into the frame of my asi2600mc. I was amazed at how many background galaxies are present so wanted to push as many subs in RGB as possible (as the moon allowed), and combined with a couple of nights worth of subs with the IDAS NBZ dual band filter.

Happy to have managed to resolve some of the cometary globules and filaments emanating radially from the central star. Apparently, there's about 40,000 of these globules, each larger than our solar system! They're much denser than the surrounding matter and moving slower than the rest of the material that's ejected - hence their unique 'comet-like' appearance.

Terrible sky conditions of the last few weeks with tonnes of high cloud and misty/foggy conditions here all over the place so the data is quite noisy, and without true narrowband data I'm really struggling to bring out those outer regions, but I'm happy to leave this one here for 2022 and maybe come back to it later for a deeper look in Ha / Oiii.

Bigger version here (https://1drv.ms/u/s!ArpSiLT3VkGHiPMNsjGxT036KQE0Kw?e= nrjdbX)

Approx 9hrs total integration
Combo data of: IDAS NBZ 30%, Optolong UHC 50%, no filter 20%
C14 non edge @f7
EQ8 pro
Asi2600mc pro
Asi290mm / celestron OAG
ASIAIR pro / APP / PS/LR

Comments & criticisms welcome. Thanks for dropping in!

[Benjamin]

Looks very natural and unforced. Really nice. Lots of detail and a lovely sense of all that radiating OIII, presumably from the dual band filter?

[Startrek]

Dave,
That’s a superb Helix
Love the iris and colour , you’ve kept some green tinge which is nice
To me the eye brows and outer faint structures are just a bit of fluff , the structures and detail of the core are what makes it click
I reckon 6 to 10 hours is enough on this object
Well done !!

Martin

[strongmanmike]

Some nice colour hues in there Dave :thumbsup:

Mike

[Dave882]

Thanks Ben I’m glad you liked the natural look cause that’s certainly where my head is at with most of my processing. I’m loathed to tinker but I had to apply some more noise reduction in this one than I’d normally like. The NBZ data helped to bring greater contrast in the core, and extended regions but there’s actually regions of dust and the cometary knots took on a more 3d appearance in broadband rgb.

[Dave882]

Appreciate your comments Martin.
I normally don’t like green nebula but really liked the colours that came through in the broadband subs (much more than in the dual narrowband filter) and thought it added to the overall picture. I actually used LR to REDUCE the saturation in this one - I felt that the core was getting overpowered and starting to kill the detail.

I’ve really struggled with the noise floor in this image. It was huge (which is why I commented on your previous post). I’m dithering every 5subs, but I can see that there’s streaks in the noise in the RA direction which tells me ASIAIR wasn’t pushing DEC enough during dithering. This has never given me an issue before in the final result. It really killed any chance of resolving fine detail in the cometary filaments.

[Dave882]

Thanks for dropping my Mike-
I started out thinking this would be a strictly dual-NB project but really changed course when I saw the rgb subs. It certainly was an interesting colour mix- probably due to the combination of filters used! But I thought it worked well to add contrast to a few different regions. Those dusty specks that form a circular pattern in the south-west region of the PN were invisible to all but the broadband subs. That and all the background galaxies!
Cheers

[strongmanmike]

Do you mean this bit?

Mike

[Dave882]

Yep that’s it. I initially was stressing that I had a dust donut, thankfully there’s a couple other shots with the same feature.

[multiweb]

Pretty neat close up David. Sharp with nice colors. You've even got some details in that small galaxy at 2 o'clock. Nice one. :thumbsup::thumbsup::thumbsup:

[Dave882]

Thanks mate. Blows me away how many galaxies are in this fov :eyepop:

[Addos]

oh man, look at that detail! aperture for the win!

[Dave882]

Thanks mate, you’re too kind! Ain’t got as much depth as your beauty but that’s where narrowband and lots of integration smashes it on targets like this. Still pretty happy how it came together. Cheers

[Addos]

true but thats only cause i threw lots and lots of gigabytes at it :P if you went as long with that beast it'd be impressive what'd be revealed! have you tried the robins egg nebula with that rig? igor did one recently at a similar fl and was able to pull quite a bit out!