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The Ghost of Cassiopeia, so difficult...puzzling
Posted: Sat Sep 24, 2022 9:06 am
by fmeireso
Hi all,
2 trial shots of this object.
I tried via NB accent module, but i just cannot get the detail out, eventually i went to L,RGB...
But i can't get the colors right. I guess it should be blue red , most pictures on the internet are like that...then again the blue/grey approach a bit like the withhead nebulae i find appealing, allthough i don't know if i stay true to the data there...
As always with most of my pictures..i just don't know it
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- IC63Gimp_ST_End.jpg (180.91 KiB) Viewed 3904 times
Re: The Ghost of Cassiopeia, so difficult...puzzling
Posted: Sat Sep 24, 2022 9:08 am
by fmeireso
And another color approach...
This is 5hr30 minutes of HA monochrome DSLR and 2:30 gr color OSC.
In any case i think i should get aleast another 4 hours of NB.
In the blue/grey version, some stars tends to go too much to the green..
Also, i could not get Navi under control, so i just cropped it out...
Boy not easy stuff...
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- IC63Cropped2.jpg (200.42 KiB) Viewed 3903 times
Re: The Ghost of Cassiopeia, so difficult...puzzling
Posted: Sat Sep 24, 2022 4:27 pm
by fmeireso
Maybe somehow a bit better, bit less cropped, and i dared to leave Navi in ...
But i NEED more data....
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- IC67Cropped2.jpg (497.14 KiB) Viewed 3882 times
Re: The Ghost of Cassiopeia, so difficult...puzzling
Posted: Sat Sep 24, 2022 5:31 pm
by hixx
Hi fmeiresco,
I think Your images are quite appealing for this challenging target....
Have You ever tried to capture with duoband (Ha /O-III) lights and load their stack into Luminance? This pushes back the stars vs the nebula so Navi will be less prone to saturate.
Then for color, create another stack with UV/IR filter lights, and load these into R&G&B. While stacking, register both stacks against the same light.
In Compose, don't create synthetic Luminance (choose L, RGB) , as the noise from the color stack would creep in.
You can also process both stacks indepndently, as the Color stack might need a stronger WIPE and combine them in Layer.
clear skies,
Jochen
Re: The Ghost of Cassiopeia, so difficult...puzzling
Posted: Sat Sep 24, 2022 5:56 pm
by Stefan B
Hi Freddy,
the last rendition looks fine to me in terms of detail but colors appear indeed a bit off in my eyes. But as you've said it's a surprisingly difficult target. I've never been happy with my result (
https://www.astrobin.com/cmzlt2/), since I wasn't able to control the stars (not to speak of Navi). But the colors I got out of the color module without much adjustments looked more reasonable (or conventional?):
Your image somehow lacks the reds in the nebula. Is your camera astro modified? If not maybe you only get the blue reflection nebula stuff so your colors would be okay I guess?
Regards
Stefan
Re: The Ghost of Cassiopeia, so difficult...puzzling
Posted: Sat Sep 24, 2022 6:04 pm
by fmeireso
Hi Jochen ,
thanks
Yes i used once my L-enhance filter with my mono DSLR to create a stack. That was of the veil nebulae cause as it turned out, with a Ha filter only much data is lost. since the Veil contains much OIII...but i did not try this on the IC 63.
So it is possible to process both stacks and combine them in layer? I never tried that , no idea how to do it actually, but that seems an interesting approach...i will have to look in to that.
Re: The Ghost of Cassiopeia, so difficult...puzzling
Posted: Sat Sep 24, 2022 6:12 pm
by fmeireso
Hi Stefan,
I always use 2 camera's, a non moded DSLR for color and a mono DSLR for HA or duoband HA/OIII for emission nebulae. Allthough this one is partly reflection too...
Color is a bit weird indeed, if i use the NBaccent approach the color comes out red and blue, better, but i can't get the detail out of it like i with the L,RGB in compose module...
And there is Navi....like Jochen said, maybe an UV/IR cut filter is required for that star...
For now i just want more data, color will remain a bit off but it might be ok for now.
Maybe not so challenging for capturing, but it sure is a challenge to process it!
Did you use the NBaccent module for your image Stefan?
Re: The Ghost of Cassiopeia, so difficult...puzzling
Posted: Sun Sep 25, 2022 9:24 am
by decay
Hi Freddy,
a few weeks ago I was also thinking about this target. But I read somewhere that it is pretty difficult and so I decided not to capture it. Maybe I have the chance to learn something here with your thread and then I will try it later.
I like your second approach most
. Of course, this seems to be the result of a strong use of the SuperStructure module, but this module is always a great help with noisy data. So as you wrote, more integration time will help for sure.
But as for the colours ... weird
fmeireso wrote: ↑Sat Sep 24, 2022 6:12 pm
a mono DSLR for HA or duoband HA/OIII for emission nebulae
I remember our discussion on your Veil Nebula thread, and I have only now understood (
) that you are using your duoband filter with your mono DSLR. Well, this means, that
you cannot distinguish between Ha and OIII, right? I will have to think it over, this thread and your Veil Nebula thread.
Have you followed Sven's M31 thread and the discussion about dark rings within stellar profiles of bright stars? I'm pretty sure, there are diffraction rings visible in Navi in your image?! I will reread Sven's thread and maybe post a hint about that ...
(What scope did you use? Was it your Askar FRA500?)
Best regards, Dietmar.
Re: The Ghost of Cassiopeia, so difficult...puzzling
Posted: Sun Sep 25, 2022 9:28 am
by decay
And don't eliminate Navi!
He belongs to us and our universe we live in, no matter, how it looks
Re: The Ghost of Cassiopeia, so difficult...puzzling
Posted: Sun Sep 25, 2022 10:22 am
by fmeireso
I remember our discussion on your Veil Nebula thread, and I have only now understood (
) that you are using your duoband filter with your mono DSLR. Well, this means, that
you cannot distinguish between Ha and OIII, right? I will have to think it over, this thread and your Veil Nebula thread.
Have you followed Sven's M31 thread and the discussion about dark rings within stellar profiles of bright stars? I'm pretty sure, there are diffraction rings visible in Navi in your image?! I will reread Sven's thread and maybe post a hint about that ...
(What scope did you use? Was it your Askar FRA500?)
Best regards, Dietmar.
Well, Startools seems to easyly distinguish the Ha en the OIII in the Veil nebulae..; I guess because the color info comes from the OSC not the mono
Colorwise the OIII part went blue and the Ha part went well at least magenta.
I had a stack of pure Ha too , clearly you see the almost missing OIII part ,
Yes Navi , is well, kind of a peculiar star, just like Alnitak ...maybe a UR/IR filter could help as allread mentioned here in this thread.
Yes , i used the ASKAR FRA 500 for this.
Anyhow, enough to tinker about.
I know this is a difficult target, but still wanted to do anyhow...because i find it so beautifull..