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Old 28-04-2021, 04:11 PM
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marc4darkskies (Marcus)
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Ngc 3981

NGC 3981 is a small spiral galaxy in Crater that's rarely imaged by amateurs and I can see why; it's a difficult target with only a small central spiral and outer reaches that are very faint! The bright central structure is only 4 x 1 arcmins. Its very faint outer structures extend to roughly 8 x 5 arcmins and suggest some kind of interaction with another galaxy long ago. Lots of tiny faint fuzzies are visible in the frame too. It's part of the NGC 4038 group, named after one of the pair of galaxies called The Antennae.

As you'd expect I can't compete with the amazing renditions done with the 8.2m ESO and other 1m class scopes in Chile; the predominant images on the web. Having said that, the main structures compare well as does the detail in the core, so I'm happy with that! Imaged over 5 nights, it was a struggle getting enough clear sky and there was much waiting with many subs thrown away due to poor seeing.

This is an LRGB image. L=360 mins, R=165 mins, G=135 mins, B=180 mins for a total of 14 hours. To be honest I need double the integration time in excellent seeing to do any better!!

The FOV (cropped for composition purposes from the full frame): 34.4 x 22.9 arcmins. Seeing was average and ranged from 1.9 to 2.6 arcsecs per pixel FWHM. Thankfully, luminance was gathered during relatively good seeing ~2.1 arcsec FWHM.

5 May: image updated with 160 minutes of synthetic luminance (Ls) to significantly improve background noise levels.

Screen sized version: https://pbase.com/gailmarc/image/171591431/original
Full Res: https://pbase.com/gailmarc/image/171591434/original
Annotated: https://pbase.com/gailmarc/image/171591432/original
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Click for full-size image (LRGB4_crop_small_annotated_ISS.jpg)
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Last edited by marc4darkskies; 05-05-2021 at 10:48 PM.
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Old 28-04-2021, 04:53 PM
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Looks wonderful Marcus
BTW only the forum image is accessible, each of the 3 hyperlinks say they require a password.

Best
JA
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Old 28-04-2021, 04:53 PM
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multiweb (Marc)
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The link (s) ask for a pwd?
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Old 28-04-2021, 04:55 PM
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How you imaged while enjoying your self at the beach has me scratching my head, but the password protected image still has me scratching
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  #5  
Old 28-04-2021, 05:16 PM
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marc4darkskies (Marcus)
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Looks wonderful Marcus
BTW only the forum image is accessible, each of the 3 hyperlinks say they require a password.

Best
JA
Hmmm, weird. I didn't set a password! Try it now.
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  #6  
Old 28-04-2021, 05:17 PM
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The link (s) ask for a pwd?
Yeah - should be good now.
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Old 28-04-2021, 06:42 PM
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ooooohhhhhhhhh niiiiice. it is a little gem
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Old 28-04-2021, 07:08 PM
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That is a sensational image! Look at that distorted halo - its massive.

I've never seen this one before.

Terrific work.

Greg.
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Old 28-04-2021, 07:43 PM
matlud (Mathew)
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Fantastic image Marcus, love the faint halo and lots of other small galaxies in the field
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Old 28-04-2021, 08:50 PM
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Yeah, rather cool image Marcus , stars do look kind'a little fuzzy, pom, pom like (seeing?) but an intriguing galaxy none the less, that I have considered hitting too, but, you know...too many galaxies, not enough time DOH!

Mike
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Old 28-04-2021, 09:43 PM
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Beautiful work Marcus. A complex and intriguing target
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Old 28-04-2021, 09:56 PM
Dave882 (David)
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Great work to get all that detail! Your patience and perseverance have really paid off!!
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Old 29-04-2021, 07:21 AM
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Way above my pay grade in skill and knowledge in terms of capture but can't argue with the result... it does look like something has move through and torn away an outer arm in the dim dark past... I always find these Galaxy shots when you start noticing even fainter background galaxies a little humbling too. Thanks for sharing Marcus.
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Old 29-04-2021, 08:48 AM
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Really nice shot. Beautiful galaxy, seriously disturbed. I really like the field color and all the faint fuzzies too. One for the cool wall.
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Old 29-04-2021, 09:38 AM
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Quote:
Originally Posted by h0ughy View Post
ooooohhhhhhhhh niiiiice. it is a little gem
Thanks Dave!

Quote:
Originally Posted by gregbradley View Post
That is a sensational image! Look at that distorted halo - its massive.

I've never seen this one before.

Terrific work.

Greg.
Much appreciated Greg! I only discovered it online myself earlier this year - I saw Adam Block's amazing rendition (using 1m scope on top of a mountain in Chile)

Quote:
Originally Posted by matlud View Post
Fantastic image Marcus, love the faint halo and lots of other small galaxies in the field
Thanks Mathew! I wish I had twice the data though (with excellent seeing) - those faint fuzzies and stars would have popped much more!

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Originally Posted by strongmanmike View Post
Yeah, rather cool image Marcus ...
Thanks Mike.

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Originally Posted by strongmanmike View Post
....stars do look kind'a little fuzzy, pom, pom like (seeing?)...
Pixel peeper alert!! Seriously? Pom poms? Yes, less than excellent seeing had an impact for sure so I deliberately went easy on my star shrinking to make sure faint fuzzies and stars weren't wiped out. And don't forget I'm imaging at 0.59 arcsecs/pix - very unforgiving with less than excellent seeing.

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Originally Posted by Ryderscope View Post
Beautiful work Marcus. A complex and intriguing target
Cheers Rodney! It was a tough one to do but I'm very pleased with how it turned out!

Quote:
Originally Posted by Dave882 View Post
Great work to get all that detail! Your patience and perseverance have really paid off!!
Thanks very much Dave. I sometimes wish deep space astrophotography was easier - but not really. I enjoy the challenge and the many hours that go into creating a nice image.

Quote:
Originally Posted by Robert_T View Post
Way above my pay grade in skill and knowledge in terms of capture but can't argue with the result... it does look like something has move through and torn away an outer arm in the dim dark past... I always find these Galaxy shots when you start noticing even fainter background galaxies a little humbling too. Thanks for sharing Marcus.
Thanks Robert! It's fun to imagine what encounters it may have had to create such disruptions

Quote:
Originally Posted by multiweb View Post
Really nice shot. Beautiful galaxy, seriously disturbed. I really like the field color and all the faint fuzzies too. One for the cool wall.
Cheers Marc, much appreciated! "Seriously disturbed" - I like that. Reminds me of me.
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  #16  
Old 29-04-2021, 09:45 AM
markas (Mark)
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Terrific result! I know from experience this is not an easy target......


Mark
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  #17  
Old 29-04-2021, 01:13 PM
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Hi Marcus, well done!
The galaxy itself looks fantastic with details, tidal streams the whole shebang!
However, I'm sorry to point this out but the larger stars look just plain wierd.
ie: the cores of the bright blue & yellow ones look pink with odd burnt in highlights, which is a distraction when everything else is exactly on point.
Might be worth another look at those.
Composition is also spot on, and well framed avoiding the standard 'plonk the galaxy in the centre of the frame' routine.
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  #18  
Old 29-04-2021, 03:43 PM
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marc4darkskies (Marcus)
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Quote:
Originally Posted by markas View Post
Terrific result! I know from experience this is not an easy target......

Mark
Thanks very much Mark! I think I'd like to do an easy target next!!

Quote:
Originally Posted by Andy01 View Post
Hi Marcus, well done!
The galaxy itself looks fantastic with details, tidal streams the whole shebang! .....
...Composition is also spot on, and well framed avoiding the standard 'plonk the galaxy in the centre of the frame' routine.
Cheers Andy, glad you liked it!! And ...

Quote:
Originally Posted by Andy01 View Post
...However, I'm sorry to point this out but the larger stars look just plain wierd.
ie: the cores of the bright blue & yellow ones look pink with odd burnt in highlights, which is a distraction when everything else is exactly on point.
Might be worth another look at those.
Aaaargh!!! How did I let that get past me!! That's what happens when you stare at an image long enough - you get blind to it's faults. I also rushed it a little. Anyway, don't apologise for giving honest and constructive feedback - you were spot on with your critique! Hopefully it's fixed now - at least improved. BTW, those stars were all saturated during the 15 minute subs. I'll go back to search for other clangers now! Thanks again!

Last edited by marc4darkskies; 29-04-2021 at 03:57 PM.
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  #19  
Old 29-04-2021, 10:51 PM
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Bingo, that's the money shot now alright!
Top stuff Maestro
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Old 30-04-2021, 12:02 PM
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marc4darkskies (Marcus)
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Bingo, that's the money shot now alright!
Top stuff Maestro
Cheers Andy!

Money shot eh? Wonder what I could get for it. 50c maybe?
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