The Heart of a Lobster

[marc4darkskies]

NGC 6357 - The Lobster Nebula (aka War and Peace Nebula) - lies about 8,000 light years away in the constellation of Scorpius.

I love the complexity of this nebula!! I reckon most so called "boring" emission nebulae have great detail just waiting to be teased out with some NB data and determined processing. The nebula comprises a complex tapestry of gas, dark dust, stars still forming, and newly born stars. The intricate patterns are caused by complex interactions between interstellar winds, radiation pressures, magnetic fields, and gravity.

This is an LLsHaRGB exposure comprising 17.75 hours of data (L=240, Ls=120, Ha=270, R=180, G=120, B=135 minutes).
FOV is 38.8 x 25.8 arcmins at 0.59 arcsec/pixel.

Screen sized version HERE (https://pbase.com/gailmarc/image/170835419/original).

Full Resolution version HERE (https://pbase.com/gailmarc/image/170835284/original).

[strongmanmike]

Nice to see a close up on this baby, it's got a lot going on for sure, so makes for an interesting scene, bit like a Where's Wally, could look at it for hours and still find new little bits :) The Pismis 24 region is always cool to make out and I'm liking the overall colour too...aaand, no sign of worms! :D Good job :thumbsup:

Mike

[Placidus]

Beautifully done Marcus. So much to see.

[Peter Ward]

Beautiful star profiles....sigh...

A pox on your pristine dark skies (again)

Yes, I like this one very much! :thumbsup:

[marc4darkskies]

Thanks Mike, much appreciated! Glad you found no worms - whatever they are! ;):lol:



Thank you M&T



Thanks very much Peter - I worked hard on this one!

Aaaand ... a pox on your Alluna in return! :P

[h0ughy]

Busy and beautiful. So much details to take in. Classy

[gregbradley]

A dramatic version of this object. Nice to see a different look,lots of detail.

Greg.

[marc4darkskies]

Cheers Houghy! Glad you liked it.



Thanks Greg! Most of these very red emission nebs have that underlying drama = detail and tonal nuance, but you need some focal length and the patience to tease it out of the data.

[PKay]

Great work Marcus

As a relative newbie, I really appreciate capture details.
You must have put in a lot of effort for this wonderful result.

Peter

[multiweb]

Superb shot Marcus. You've got that little spire and the cluster in the middle clearly resolved. :thumbsup:

[Andy01]

Nice result, good details & very bold colours! :thumbsup:
Some funky star colours there though, have you considered just using the RGB stars? :question:
IMO it would make an even stronger image. :D

[marc4darkskies]

I sure did! Ha/RGB blends are quite tricky to do perfectly!



Thanks very much Marc! I'm pleased with the detail I got there!



¿Qué? Use RGB stars? They ARE RGB stars - it's an RGB based image. :shrug:

I can only assume you meant the relative abundance of small red stars like the ones near the centre of the image and in the red neb? Such things do happen with an HaRGB blend. It's very hard to isolate tiny stars from the blend processing to avoid blowing out the colour sats. I.e. they got dragged along in the chain of processing and ended up getting a bit too saturated.

In any case I've taken your critique to heart and modified the stars using the original RGB stars layer. This isn't a perfect solution but it makes a very small but noticeable difference ... if you're a Picky Pixel Peeper! :lol: Don't worry, I'm a PPP myself! :help:

PS: I hope you're looking at it on a calibrated monitor - I just noticed my phone makes the stars look horrible!

[Andy01]

Much nicer! :thumbsup:
...and yes, as I'm a working professional photographer my industry standard Eizo monitor is properly calibrated. :D

[marc4darkskies]

Thanks Andy you had me puzzled there for a bit! :lol: I'm glad you noticed a difference - it was a very subtle change.

Enhancing LRGB with Ha is tricky - you have to layer Lum into Ha as a lighten layer, then layer Ha into the R (~30-50% as lighten) and B (~10-20% as lighten layer) channels. In all that you need to restore the RGB star colours because they become corrupted. Which I did do but obviously noooot quite enough! :) Thank you for being my PPP conscience! :D

I also have an Eizo but I'm thinking of getting a second - one monitor is just not enough! :D

[topheart]

Wow! Awesome work Marcus!

Spectacular and dramatic!

Cheers,
Tim

[Bart]

That is lovely, Marcus!



Can you tell me what is Ls?

[marc4darkskies]

Thanks a lot Tim! I always love a bit of drama! :D



Thanks mate.

Ls is short for Synthetic Luminance. If your RGB combine is good quality, then it's useful to change it to grayscale and combine it with your Luminance to improve S/N.

[marc4darkskies]

So I was curious about the stars in the Pismis 24 open star cluster and a little confused about what the masses of these stars were. So with a little digging I found a good article, most of which went over my head:
"Star formation and disk properties in Pismis 24"
Article in Astronomy and Astrophysics · January 2012

I'm not sure whether this information is still current but it'll do! If anyone can provide updated info please do so!

Full res versions can be found HERE (https://pbase.com/gailmarc/image/170841585/original) and the annotated version HERE (https://pbase.com/gailmarc/image/170843222/original)

[strongmanmike]

Might be rather hard to survive in the middle of that bunch of beasts :scared:

Mike

[marc4darkskies]

SPF 1,000,000 should do it! :lol: