Go Back   IceInSpace > Images > Deep Space
Register FAQ Calendar Today's Posts Search

Reply
 
Thread Tools Rate Thread
  #1  
Old 19-10-2015, 07:49 PM
Paul Haese's Avatar
Paul Haese
Registered User

Paul Haese is offline
 
Join Date: Jan 2009
Location: Adelaide
Posts: 9,991
NGC253, reprocess and more data

My last process of this data revealed lots of detail and some of the halo but I was not overly happy with the results. It looked too contrasted and the colour was dark blue/red. So I collected a bit more data in the colour and reprocessed the data from scratch. My question is what is the actual colour of this galaxy? It's a rhetorical question really.

All I did to answer this question in my mind is push the saturation and boost the contrast a bit but not too much.

I think the colour looks more natural than my previous rendition and the halo is a lot brighter.

Click here for image

PS while it might seem like another in the plethora of NGC253's, I remember when Centaurus A was almost the only image in this part of the forum.
Attached Thumbnails
Click for full-size image (NGC253 LRGB 520 140 120 120 final.jpg)
184.2 KB190 views

Last edited by Paul Haese; 19-10-2015 at 08:01 PM.
Reply With Quote
  #2  
Old 19-10-2015, 07:51 PM
gregbradley's Avatar
gregbradley
Registered User

gregbradley is offline
 
Join Date: Feb 2006
Location: Sydney
Posts: 18,185
That's a fantastic image Paul. The blue areas are positively glowing which looks fantastic. The yellow core looks very luminous. An image to be proud of.

Greg.
Reply With Quote
  #3  
Old 19-10-2015, 08:01 PM
RickS's Avatar
RickS (Rick)
PI cult recruiter

RickS is offline
 
Join Date: Apr 2010
Location: Brisbane
Posts: 10,584
I don't know what colour NGC 253 really is but that looks great, Paul

Cheers,
Rick.
Reply With Quote
  #4  
Old 19-10-2015, 08:03 PM
codemonkey's Avatar
codemonkey (Lee)
Lee "Wormsy" Borsboom

codemonkey is offline
 
Join Date: Jul 2013
Location: Kilcoy, QLD
Posts: 2,058
That's awesome Paul; love it! I was going to ask how much data, but I saw it's on your site ;-)

Very smooth, love the colour, and, well, everything...
Reply With Quote
  #5  
Old 19-10-2015, 08:15 PM
Peter Ward's Avatar
Peter Ward
Galaxy hitchhiking guide

Peter Ward is offline
 
Join Date: Dec 2007
Location: The Shire
Posts: 8,484
What's not to like? A top shelf rendition for sure.
Reply With Quote
  #6  
Old 19-10-2015, 08:22 PM
Stevec35 (Steve)
Registered User

Stevec35 is offline
 
Join Date: Aug 2010
Location: Canberra
Posts: 3,654
Hi Paul

I have to admit I'm getting a little over NGC 253 but that's a high quality image to be sure.

Cheers

Steve
Reply With Quote
  #7  
Old 19-10-2015, 08:24 PM
E_ri_k (Erik)
Registered User

E_ri_k is offline
 
Join Date: Jun 2011
Location: Lakes Entrance
Posts: 846
Looks great Paul, love the colours. A fine image indeed.
Erik
Reply With Quote
  #8  
Old 19-10-2015, 08:42 PM
alpal's Avatar
alpal
Registered User

alpal is offline
 
Join Date: Jan 2012
Location: Melbourne
Posts: 3,786
Hi Paul,
that is a superb image.
I love the colours.
What else could you do - maybe add some Ha subframes?


cheers
Allan
Reply With Quote
  #9  
Old 20-10-2015, 08:43 AM
Paul Haese's Avatar
Paul Haese
Registered User

Paul Haese is offline
 
Join Date: Jan 2009
Location: Adelaide
Posts: 9,991
Thanks Greg, Rick, Lee, Peter, Steve and Erik for your comments. I think I can finally put this one to bed now. Bit tired of staring at it too.

Quote:
Originally Posted by alpal View Post
Hi Paul,
that is a superb image.
I love the colours.
What else could you do - maybe add some Ha subframes?


cheers
Allan
Thanks Allan, I don't think I am going to go down the Ha sub frames route at this time. Maybe next year I will collect that and add to some more luminance to collect more data on the back ground galaxies.
Reply With Quote
  #10  
Old 20-10-2015, 09:23 AM
Placidus (Mike and Trish)
Narrowing the band

Placidus is offline
 
Join Date: Mar 2011
Location: Euchareena, NSW
Posts: 3,719
Hi, Paul,

Good before, but the colour is now utterly superb. The colour in the outermost, non-star-forming super-faint area is much better, as is the colour in the distant galaxies, which also seem a tad sharper.

There might be some resultant and inevitable loss of contrast in the beautiful galactic fountain dust streamers, but your streamers are still unbelievably sharp and clear - lovely processing and something to aspire to.

Best,
Mike
Reply With Quote
  #11  
Old 20-10-2015, 12:54 PM
Slawomir's Avatar
Slawomir (Suavi)
Registered User

Slawomir is offline
 
Join Date: Sep 2014
Location: North Queensland
Posts: 3,240
Looks really really great, worthy printing IMO
Reply With Quote
  #12  
Old 20-10-2015, 01:34 PM
Paul Haese's Avatar
Paul Haese
Registered User

Paul Haese is offline
 
Join Date: Jan 2009
Location: Adelaide
Posts: 9,991
Quote:
Originally Posted by Placidus View Post
Hi, Paul,

Good before, but the colour is now utterly superb. The colour in the outermost, non-star-forming super-faint area is much better, as is the colour in the distant galaxies, which also seem a tad sharper.

There might be some resultant and inevitable loss of contrast in the beautiful galactic fountain dust streamers, but your streamers are still unbelievably sharp and clear - lovely processing and something to aspire to.

Best,
Mike
Thanks Mike, there is always a balancing act between contrast and brightness I think. I went back to look at the original image many times and in the end I just thought it needed a reprocess. I kept thinking it looks too dark and the halo is not well shown.

I don't think the streamers are as good as those shown by Jay Gebany in his image but I think my image gives a little of everything.

I did sharpen the background galaxies just a little and that is well spotted.

Quote:
Originally Posted by Slawomir View Post
Looks really really great, worthy printing IMO
Thanks Slawomir, the first version appeared in this months A&T. It looked ok but a little dark. This should look better.
Reply With Quote
  #13  
Old 20-10-2015, 02:27 PM
Camelopardalis's Avatar
Camelopardalis (Dunk)
Drifting from the pole

Camelopardalis is offline
 
Join Date: Feb 2013
Location: Brisbane
Posts: 5,479
A mighty fine 253 if ever I saw one if it wasn't for you guys pushing the boundaries some of the rest of us wouldn't have as much to aspire to!
Reply With Quote
  #14  
Old 20-10-2015, 03:04 PM
topheart
Registered User

topheart is offline
 
Join Date: Nov 2005
Location: Cairns
Posts: 1,087
Nailed it!



Tim
Reply With Quote
  #15  
Old 21-10-2015, 08:49 AM
Paul Haese's Avatar
Paul Haese
Registered User

Paul Haese is offline
 
Join Date: Jan 2009
Location: Adelaide
Posts: 9,991
Quote:
Originally Posted by Camelopardalis View Post
A mighty fine 253 if ever I saw one if it wasn't for you guys pushing the boundaries some of the rest of us wouldn't have as much to aspire to!
Thanks Dunk, its good to push the boundaries of what has been achieved so far. No doubt this will continue to improve every where across the imaging world.

Quote:
Originally Posted by topheart View Post
Nailed it!



Tim
Thanks Tim, still think it could do with a few more hours, but there are more pressing targets on the list that need attention now.
Reply With Quote
  #16  
Old 05-11-2015, 08:59 PM
Shiraz's Avatar
Shiraz (Ray)
Registered User

Shiraz is offline
 
Join Date: Apr 2010
Location: ardrossan south australia
Posts: 4,918
pretty much as good as it gets Paul.

The only slight niggle is the asymmetric colour in the halos of the brightest stars - might be worth desaturating them slightly - but that really is nit picking in the extreme.
Reply With Quote
  #17  
Old 06-11-2015, 12:20 PM
Paul Haese's Avatar
Paul Haese
Registered User

Paul Haese is offline
 
Join Date: Jan 2009
Location: Adelaide
Posts: 9,991
Quote:
Originally Posted by Shiraz View Post
pretty much as good as it gets Paul.

The only slight niggle is the asymmetric colour in the halos of the brightest stars - might be worth desaturating them slightly - but that really is nit picking in the extreme.
Thanks Ray. It is kind of weird why this happened. I remember looking at these stars during processing and trying to determine the colour of the three main bright ones. Some images show them as blue and some show them as orange. I will need to consult with a star catalogue to get the actual star spectral type. However, that does not explain how this asymmetric colouring has occurred. I suspect it is just a bit of miss alignment and you have quite rightly pointed it out. I had forgotten about them and considered them as white noise. Time to sort that out and actually find out why that occurred.

Edit: I have just reduced this problem a little bit so it is now not as evident.

Last edited by Paul Haese; 06-11-2015 at 12:30 PM.
Reply With Quote
  #18  
Old 06-11-2015, 12:46 PM
marc4darkskies's Avatar
marc4darkskies (Marcus)
Billions and Billions ...

marc4darkskies is offline
 
Join Date: Mar 2007
Location: Quialigo, NSW
Posts: 3,143
That's strange, I thought I'd already commented on this

In any case, though probably just a little too saturated for my taste, it's an excellent image Paul!

Cheers, Marcus
Reply With Quote
  #19  
Old 06-11-2015, 02:06 PM
Paul Haese's Avatar
Paul Haese
Registered User

Paul Haese is offline
 
Join Date: Jan 2009
Location: Adelaide
Posts: 9,991
Quote:
Originally Posted by marc4darkskies View Post
That's strange, I thought I'd already commented on this

In any case, though probably just a little too saturated for my taste, it's an excellent image Paul!

Cheers, Marcus
Thanks Marcus. I think you commented on the previous rendering of this data.

I dropped back the saturation just a little. I think that looks better too. It's always interesting to see what others see in an image.
Reply With Quote
  #20  
Old 06-11-2015, 05:54 PM
Shiraz's Avatar
Shiraz (Ray)
Registered User

Shiraz is offline
 
Join Date: Apr 2010
Location: ardrossan south australia
Posts: 4,918
looking good. just for interest, the two bright stars are B-V of 0.6 and 0.57, which means they are pretty close to the sun - ie pastel yellow (http://www.vendian.org/mncharity/dir...r/details.html). The renditions that show them as blue or orange are taking some liberties with the light .

FWIW, I have had colour oddities on very bright stars when taking colour data on different sides of the meridian - I assume that the scope flexes slightly and the diffraction skirts of the brightest stars do not match up precisely if one colour is taken on a different side from the other two. I haven't tested the theory, since it has only happened occasionally and is easy enough to tidy up.

Last edited by Shiraz; 06-11-2015 at 06:18 PM.
Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +10. The time is now 08:01 PM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Advertisement
Astrophotography Prize
Advertisement
Bintel
Advertisement