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Nikolas
26-11-2023, 09:51 AM
Large Magellanic cloud incorporating the Tarantula Nebula and all the Globules. Despite it being a satellite galaxy it is full of interesting stellar matter. If the Tarantula nebula was in the same region as Orion it would cover a much larger part of the sky it is HUGE.
6 panel mosaic in total with much overlap average of 3 hours per panel of 5 minute subs
Shot with the ZWO asi 294mc Pro
Optolong L-Ultimate filter
Telescope: Askar FRA300 pro
Combined and stacked with Astropixel Processor, processed in Pixinsight and Photoshop
Mosaic organised and acquired in the ZWO asiair and used it with beltmodded Skywatcher Neq6
This has taken 6 weeks to complete due to the weather and work. I'm not 100% happy but will revisit it when I have time.


Would really appreciate some constructive criticism



Astrobin link
(https://www.astrobin.com/tl8q51/)

strongmanmike
26-11-2023, 01:13 PM
Wow Nik, that's fantastic, great work on a great project very nicely done :thumbsup:

Look at all those swatted flies, bug strikes and skin blemishes, everywhere! :eyepop:

Awesome

Mike

pmrid
26-11-2023, 03:48 PM
Great work Nik. One of my dearest imaging targets. Green with envy.

Dave882
26-11-2023, 04:11 PM
Amazing image mate. Wow there’s a lot going on :eyepop:

Startrek
26-11-2023, 05:44 PM
Brilliant image Nik
Don’t touch a thing
Well done for hard work and creativity alone

Cheers
Martin

JA
26-11-2023, 05:51 PM
Absolutely Magic Nik - Well done :thumbsup::thumbsup:

Best
JA

Nikolas
26-11-2023, 07:02 PM
Thanks everyone, Does it look too muddy?

Nikolas
26-11-2023, 09:58 PM
I've also added a second image
Which one is more preferable?
This took some tweaking with the green and blue channels

Startrek
26-11-2023, 10:21 PM
Nik,
My preference is still the original
The GB saturation tends to be a bit too strong in certain areas
Only my opinion
Either image is still excellent

Martin

alpal
26-11-2023, 11:03 PM
Hi Nik,
it's a great mosaic.

To me it looks a little dark.
If the curves in Photoshop are moved up at about the level of
110 bits out of 255 bits then it will brighten the picture up.

As for the colors - every picture I see of the LMC or Tarantula is different.
You have less control with a colour camera and some other people
have used a mono with obviously different LRGB filters and
then given them different weights in the processing.
Look at all the different pictures and different colors here:
https://www.constellation-guide.com/tarantula-nebula-30-doradus/

I would probably trust this Astrodon filter LRGB picture for the colors:
https://www.astrobin.com/2denjq/?q=%22HD269922%22

cheers
Allan

Ryderscope
27-11-2023, 07:52 AM
A wonderful and ambitious project Nik. I agree with Allan that a small tweak in brightness would be beneficial. It’s good to see the results appear on the screen after all your hard work bringing this together. You should be happy with that scope and camera combination.

Nikolas
27-11-2023, 09:05 AM
Yep Thanks for the feedback I think I'll stick with the original and brighten it up a bit see how we go. It really needs more data as some panels got twice the data as some of the others.


Anyways I have posted a third version brightened up and very very mildly tweaked the reds so it's less muddy

strongmanmike
27-11-2023, 10:25 AM
The kiiiinda true RGB type palette present in the brightest part of the 30 Doradus Tarantula complex, should probably be some sort of red-blue-green (https://www.astrobin.com/full/207587/0/) combination...but colouring, contrast and hue in narrow band..?..that's a different story and has so many levers. In the end the palette and overall "look" settled on, comes down to simply what you like the look off, personally, everyone has differing tastes. My eye sees a definite J-P Metsavainio (https://astroanarchy.blogspot.com/) palette influence in this case, which looks pretty good :thumbsup:.

Mike

Nikolas
27-11-2023, 11:12 AM
Agree mate
I have seen many narrowband versions and many of them look like my final edit, could this region be like this because of the distance and maybe the dust?
LRGB doesn't bring out most of the HA and there is a real large amount of HA in there. I'm not sure

strongmanmike
27-11-2023, 11:38 AM
I see you used the dual band filter, I'm not sure how this affects colour balance, as it is letting in both the Ha and OIII bands together and nothing else..? How do you separate the two channels, in terms of processing to get a colour image? Dust is not revealed when using NB filters, only emission gets through, although some dust does have a tiny bit of Ha in it so does emit some light but I wouldn't think it would contribute much if anything to the colour palette..?

Mike

alpal
27-11-2023, 01:40 PM
Hi Mike,
I hadn't realised that Nik had been using the Optolong L-Ultimate 2" filter.
Of course the colors will be different to an LRGB picture.
It's only passing 2 narrow bands:
https://cdn.shopify.com/s/files/1/0071/4935/5059/files/L-Ultimate_transmission_800.png

There are some hints on how to process the picture here:
https://www.youtube.com/watch?v=740ZLTe95eg

cheers
Allan

Nikolas
27-11-2023, 02:01 PM
Hi Mike I find the dust really comes out with the narrowband filter, maybe it is ionized by the HA I'll post an image taken of M42 taken with the Optolong L-Ultimate to give you an idea of what I can pick up in bortle 6 skies as compared to broadband of the same target, yes the O2 is muted but using Pixinsight and some of the newer tools and techniques utilised by the likes of Lucomatico and Dark rangers youtube sites I amdslowly adding to the workflow. It's quite the process.
this m42 was only 3 hours of 180 second subs Processed in pixinsight and photoshop. It's a little soft as I was testing my eq3 which wasnt that good at the time

strongmanmike
27-11-2023, 03:59 PM
Pretty sure all that material in your photo is actually emission from ionised gas...? :question: The dust is in the areas that are essentially black, ie the gaps where it looks like there is nothing, in and around the emission...? There may be dust mixed in with the ionised gas but dust doesn't emit light only reflects it, so it is not being picked up through a narrowband filter, or something like that anyway...maybe I am missing something? maybe the dust can reflect some of the emission line light?..:question:

A good way to test it would be to use the same filter to take an image of say, Corona Australis or The Pleiades and see what it looks like compared to a broader band image?

Mike

Nikolas
27-11-2023, 04:34 PM
I tried it with Corona Australis and not much to see, Unfortunately trees block the pleiades for me

SB
28-11-2023, 03:09 PM
Wow Nik,
That is really nice!

Chris

AstroViking
28-11-2023, 04:00 PM
I can't offer anything constructive, sadly, other than "Bloody hell that's a lot of spots and dots."

Excellent image, Nik, Very, very well done.

Nikolas
28-11-2023, 05:33 PM
Thanks Chris










Damn I knew I had to clean the sensor! LOL