Helix HNO

[Slawomir]

Hi all,

First of all, thank you all for your feedback and encouragement with this project. I did not plan to do any unusually long for me integration, but as the project went on I wanted to see how my camera and telescope behave with longer total exposure. It has proven to be quite a tough object to process. I am not quite pleased with the final result, but having gone through literally tens of revisions I think I need a longer break and may try a different colour approach one day in the future.

Some acquisition details:

Telescope: CFF 105mm with a Riccardi reducer (imaging at f/4.5)
Camera: QSI 690
Filters: 3nm Ha (201 x 900s), 3nm OIII (124 x 900s) and 3nm NII (88 x 900s).

Although processing still have plenty of room for improvement, I tried to respect each and every photon by not doing decon, not removing stars and by applying only a touch of noise reduction. I combined Ha, OIII and NII into a Luminance - it resulted in an improved overall NSR (background noise is only 0.17e!) at the expense of washing out some interesting structures near the core due to strong signal in OIII and perhaps making outer bows and shockwaves a tad fainter.

Links to Astrobin:

V1 - Conservative processing: https://www.astrobin.com/full/364378/B/?nc=user

V2 - A bit more adventurous processing: https://www.astrobin.com/full/364378/C/?nc=user

V3 - Darkened background: https://www.astrobin.com/full/364378/D/?nc=user

V4 - More colour: https://www.astrobin.com/full/364378/E/?nc=user

V5 - More noise reduction: https://www.astrobin.com/full/364378/F/?nc=user

V6 - Final result: https://www.astrobin.com/full/364378/G/

Thank you for looking
Suavi

[RickS]

Hi Suavi,

That's impressively deep but I agree it looks a little washed out in the core. I also can't agree that decon is disrespectful, at least not when used with moderation :lol:

Cheers,
Rick.

[Geoff45]

Nice, deep and intricate Suavi. Agree with Rick about the decon—after all, decon attempts to recover real detail that has been smeared by the atmosphere.

[strongmanmike]

Yes perhaps some more punch could be had with upping the contrast and colour fidelity and maybe some highpass/sharpening :question: (not necessarily decon though :eyepop: ;))

I like the delineation of the three wavelengths

Some apt words for this image are: Honest, quality data, clean, crisp, real, subtle, balanced and deep :)

Nice job Suavi, this object is imaged to death :scared: so well done on producing something worth browsing for a while..not to mention following its development :thumbsup:

Mike

[Placidus]

Astoundingly good.

We're thrilled that your helix and our Ha-only version seem to show the same faint structures. They really are up there.

After seeing your image, it seems we over-processed ours. Yours is better. And of course, it has OIII and NII, which is a real coup.

Best,
MnT

[Slawomir]

Thank you Rick, Geoff, Mike and Mike and Trish for your kind words.

I agree that by trying to preserve photon information as much as possible, I created a rather mundane result colour and detail wise.

This (https://www.astrobin.com/full/364378/C/?nc=user)version has bit treated with a good dose of Local Histogram Equalisation and a tad of sharpening. I think I like it more than the more conservative original image.

Thank you for looking.
Suavi

[gregbradley]

I really like the adventurous processing version. It has a nicer colour balance to my eye.

Nicely done and quite a unique look. Well worth the effort.

Greg.

[cometcatcher]

I like the adventurous one too. Very detailed.

[Ryderscope]

This has been a great project Suavi. Thank you for sharing it with us.

[billdan]

Wow, that looks really good Suavi. The NII really makes a difference to the traditional bi-colour image we usually see.

[Andy01]

Interesting stuff and quite a remarkable journey to get there!
I kinda miss the classic Suavi punch in the processing though - I reckon you should let the hounds loose and really let all that monster data sing. :lol:
Congratulations on the image anyway, well done! :thumbsup:

[Slawomir]

Thank you Greg, Kevin, Rodney, Bill and Andy for such kind feedback.

I may yet attempt to create an even more adventurous V3 in the near future :-)

[Atmos]

:eyepop:

Been checking this out on my phone over the last few days and waiting till I arrived back home to view it on my laptop.
Excellent job Suavi!

The colour is certainly different but I've never seen it in HNO which is really interesting. At 100 hours that is pretty staggering, considerably more clear nights than we get down here :lol:

[Slawomir]

Glad you like it Colin.

The colour palette is not a straight HNO since I played a bit with curves - putting together Ha, OIII and NII in all possible combinations did not produce any pleasing colours and I resisted blending on this occasion.

I also slightly tweaked V2, mainly to darken background a notch: https://www.astrobin.com/full/364378/E/?nc=user

Thank you for looking!
Suavi

[strongmanmike]

You can't please everyone Suavi, what you have produced is clearly a quality and interesting image, the level of dynamic structure is matched by very few other versions out there, hearty congrats from me :thumbsup:

Mike

[Slawomir]

Thank you Mike.

I agree that we cannot please everyone and we probably should not even try. Having said that, I really appreciate everyone's feedback and like reading comments from fellow astronomers. And I also like going back to the data that in some cases took many nights to acquire, and to have multiple goes at processing, experimenting and maybe even improving the image.

Speaking of redoing processing, here is Version #5: https://www.astrobin.com/full/364378/F/?nc=user

:lol:

[astronobob]

Thats an amazing Image, Suavi, depth & Detail are up there with the best in my honest opinion :cool2:

[Placidus]

The "Bit more adventurous" one is truly magnificent. You've preserved all the super-faint stuff, but brought out strong and 3D-looking details in the brighter section. Stunning work.

[Slawomir]

Thank you Bob - really appreciate your feedback.



Thank you Mike and Trish. I also like images gently processed, but at the same time I enjoyed experimenting with noise reduction and seeing what it does to the data.

Speaking of experimenting, I think I am ready to settle on Version 6: https://www.astrobin.com/full/364378/G/ (https://www.astrobin.com/full/364378/G/?nc=user) :lol:

[multiweb]

I don't recall seeing a NB color shot that deep on it. Quite a challenge. I tried to go deep in Ha from home and I know exactly how difficult it is to get these shock fronts smooth. Top shelf. :thumbsup::thumbsup::thumbsup:

[Ross G]

A great looking photo Suavi.


Amazing depth and detail.


Ross.

[Slawomir]

Thank you Marc. It was a fun experiment to get to my first century in terms of integration.



Thank you Ross. It was a challenging object and I have learnt a few things about my rig and data processing during this project.