Soul Nebula (+ more fretting about duoband colors!)

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dx_ron
Posts: 227
Joined: Fri Apr 16, 2021 3:55 pm

Soul Nebula (+ more fretting about duoband colors!)

Post by dx_ron »

Soul_w-rgb-stars_2560_700k.jpg
Soul_w-rgb-stars_2560_700k.jpg (695.89 KiB) Viewed 56916 times
AT65EDQ. My first image with the L-Ultimate (3nm) instead of the AlpT (5nm). I think the 40% shrink in passband helped, so I will be keeping the L-Ultimate and selling the AlpT.

132x300s (11 hours) duoband, plus 120x30s RGB for the stars.

Processed entirely in ST. The duoband coloring comes from a combination of reducing green + jacking blue way up, followed by 3 or 4 hits with the "Saturate visual Oiii" stick. This maybe isn't a great test case, because there's quite a lot of Oiii in this nebula. Anyway - it is blue, though not the really vibrant (almost 'electric') blues Freddie gets with gimp.

I feel like I am getting better at Layering in the stars. I made the mask on the b&w but denoised RGB image, with the Threshold down a fair bit to catch the glow around larger stars. Then I hit Grow a couple of times to give a buffer region for a large (~10 pixel) mask fuzz in the Layer module.

Freddie - if you find yourself cloudy and bored, here's a link to the tiff file from the duoband. I'd be curious what you can make out of it (and even more curious *how*!). https://www.dropbox.com/s/qqykja37avb29 ... .tiff?dl=0

Happy Thanksgiving to us in the US!
fmeireso
Posts: 365
Joined: Mon Sep 28, 2020 8:46 pm
Location: Belgium

Re: Soul Nebula (+ more fretting about duoband colors!)

Post by fmeireso »

Hi Ron,

Here is a first trial. i made some mistakes doing. The stars are less good and i left too many out, resulting in a right Soul part that should have still the stars in...

Anyway

To get the blue in, is actually not difficult.
In Gimp : Curves histogram, green curve, lower it. The blue should already turn up.
Color balance : midtones put Cyan to left.

this what I got after that
Soul_ult_132x300s_v1Gimp (Large).jpg
Soul_ult_132x300s_v1Gimp (Large).jpg (473.09 KiB) Viewed 56876 times

Off course then you get ugly blue stars and too blue background.
So i made a starless image with Starnet v2 but from (sorry) Pixinsight because there you can have both the stars image and the nebulae image separatly in one go.

And then you can work on both the starfield and nebulae for more pleasing colors in GIMP using hue saturation. Heck , you can even run the stars through the color module of Startools again and find out if you can get descent starcolor again.

Then to put everything back ,one has to use the layer module of Startools . Open a star image, then goto layer and open the nebulae only. then use Lighten and see what you get.

The image here is just an example, it can be much better, i made some mistakes but it is only to give you an idea to get the blue out.
Maybe all a bit unconventional but well i dunno ..it is a hobby ... :D and it keeps you busy during the never ending rainy days ;)
Soultresult (Large).jpg
Soultresult (Large).jpg (339.16 KiB) Viewed 56876 times
I understand now you got your stars from an RGB image, they are quite nice. That is indeed the way to go for duoband imho. i wondered how you got these starcolors. I missed it in my first reading through...
fmeireso
Posts: 365
Joined: Mon Sep 28, 2020 8:46 pm
Location: Belgium

Re: Soul Nebula (+ more fretting about duoband colors!)

Post by fmeireso »

Ron, i noticed the link to the picture is not the one that is posted ,is it...? The linked tiff has no RGB stars.
fmeireso
Posts: 365
Joined: Mon Sep 28, 2020 8:46 pm
Location: Belgium

Re: Soul Nebula (+ more fretting about duoband colors!)

Post by fmeireso »

Another try at it .... and btw it is great data...imho
Image03_3End (Large).jpg
Image03_3End (Large).jpg (448.6 KiB) Viewed 56865 times
dx_ron
Posts: 227
Joined: Fri Apr 16, 2021 3:55 pm

Re: Soul Nebula (+ more fretting about duoband colors!)

Post by dx_ron »

Hi Freddie, yes, the file I linked is without the rgb stars because any nebula color-cheating needs to be done before layering in the stars, or the star colors will get all out of kilter and everyone will know I've been playing rude games with the nebula.

Thanks for pointing me in general directions in gimp. One thing that bothered me about the image is that pushing blue so hard in ST was turning the lower-left corner blue - but that is the outer reaches of the Heart and is definitely Ha. So I went back and re-processed from scratch and produced an ST starting point where that bit is still reddish.

Now I'm like a kid playing with new toys in gimp he doesn't quite understand - who knows what crazy things will keep coming out? I kind of like this one so far:
Soul_ult_132x300s_gimp-test3.jpg
Soul_ult_132x300s_gimp-test3.jpg (687.13 KiB) Viewed 56851 times
fmeireso
Posts: 365
Joined: Mon Sep 28, 2020 8:46 pm
Location: Belgium

Re: Soul Nebula (+ more fretting about duoband colors!)

Post by fmeireso »

Yes, Ron I think you are on the right track. Off course you will have to experiment to find out how things work a little bit in GIMP. I only use it for adjusting some coloring, hue, saturation and stuff like that. I also experienced that is you don't have something descent out of Startools, GIMP will not work miracles either...
dx_ron
Posts: 227
Joined: Fri Apr 16, 2021 3:55 pm

Re: Soul Nebula (+ more fretting about duoband colors!)

Post by dx_ron »

Unsurprisingly, I made another attempt in gimp and wound up in a different place. I need to figure out some way to keep track of gimp manipulations.

The starting point was different, also. I was unhappy with the excessive noise in the outer reaches of nebulosity so I started over with a less aggressive stretch in Optidev. I think this is OK-ish
Soul_ult_nb-Wipe_small-RoI_bin-after-svd_dim+nr_v2_gimp1_with-stars.jpg
Soul_ult_nb-Wipe_small-RoI_bin-after-svd_dim+nr_v2_gimp1_with-stars.jpg (697.54 KiB) Viewed 56266 times
decay
Posts: 406
Joined: Sat Apr 10, 2021 12:28 pm
Location: Germany, NRW

Re: Soul Nebula (+ more fretting about duoband colors!)

Post by decay »

This last one looks fantastic, Ron :thumbsup: Too bad that it is based upon such a terrible (H)euristic (AL)gorithm ;-)

Dietmar.
dx_ron
Posts: 227
Joined: Fri Apr 16, 2021 3:55 pm

Re: Soul Nebula (+ more fretting about duoband colors!)

Post by dx_ron »

Thanks!

(R)andom (O)verstressed (N)eurons
fmeireso
Posts: 365
Joined: Mon Sep 28, 2020 8:46 pm
Location: Belgium

Re: Soul Nebula (+ more fretting about duoband colors!)

Post by fmeireso »

Looks great!

CS
Freddy
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