Go Back   IceInSpace > Images > Deep Space

Reply
 
Thread Tools Rate Thread
  #1  
Old 19-10-2017, 01:16 PM
Placidus (Mike and Trish)
Narrowing the band

Placidus is offline
 
Join Date: Mar 2011
Location: Euchareena, NSW
Posts: 3,719
Arp 93 - faint features in the tidal tail

NGC 7284 and 7285 are two small galaxies (each about 2.5 by 1.5 min arc), middling faint (each mag 12, 13 mag/sq arcmin), so difficult targets, and not often imaged, but interesting because they are tearing each other to shreds.

Aspen CG16M on 20" PlaneWave. Lum 9.5 hrs, RGB 2 hrs each in half hour subs. Field 0.36 min arc, north up. No moon, but very windy and variable seeing.

The thumbnail is a tight crop. The full image, which contains many other interesting furry creatures, is here.


There are only two other comparable images that we could find: a recent and beautiful work by Mike Sidonio, which is extremely sharp, and a quickie by the Carnegie-Irvine Galaxy Survey using a 2.5 metre scope in Chile, which is ridiculously sharp but not very deep.

Our image is much deeper than the CGS image , but of course nowhere near as sharp. We're pleased to see that our colours are comparable, and that we don't seem to have produced too many dots that aren't also in the CGS image.

In our image, the broad tidal tail toward 7 o'clock proves to be leaf-shaped, with three identifiable bluish vein-like streamers of star formation, not easily photographed because of their faintness.

Very best,
Mike and Trish
Attached Thumbnails
Click for full-size image (Arp 93 L 9h30m RGB 2 hrs each thumb.jpg)
156.3 KB95 views

Last edited by Placidus; 19-10-2017 at 01:28 PM.
Reply With Quote
  #2  
Old 19-10-2017, 01:57 PM
Peter Ward's Avatar
Peter Ward
Galaxy hitchhiking guide

Peter Ward is offline
 
Join Date: Dec 2007
Location: The Shire
Posts: 8,090
Suspect the seeing let you down, but love the depth of the image.
Reply With Quote
  #3  
Old 19-10-2017, 02:03 PM
willik (Willik)
Registered User

willik is offline
 
Join Date: Nov 2009
Location: Perth WA
Posts: 715
A little bit out of focus but still a very nice image not a easy target
Martin
Reply With Quote
  #4  
Old 19-10-2017, 02:15 PM
strongmanmike's Avatar
strongmanmike (Michael)
Highest Observatory in Oz

strongmanmike is offline
 
Join Date: May 2006
Location: Canberra
Posts: 17,150
Great stuff guys, never before seen on IIS and now twice in under a month

Very interesting to compare our results actually, looking at the more diffuse extensions there is little or no difference in depth but as expected, the superior aperture has snuck just a little deeper on point sources...although, I don't apply decon to my star fields so there are probably some faint stars lurking in the background of my data?..I just hate spots in my background that you can't distinguish form stars. Comparing the detail in some surrounding galaxies I may just have had a little better seeing?.. oooor, we just used different processing approaches..? As you say, you look to have revealed some detail in the leading (left) edge of the main fan shaped tidal tail, which although subtle is indeed very cool. I am thinking from the look of the rest of the image, you used some solid extraction techniques here..? which is also cool, I love heavy extraction to go deep and reveal new things! ...image noise is overrated!

Overall another great use of a great instrument guys and great to see big high end equipment hitting interesting things, rather than the same ol samo

Mike
Reply With Quote
  #5  
Old 19-10-2017, 02:26 PM
RickS's Avatar
RickS (Rick)
PI cult recruiter

RickS is offline
 
Join Date: Apr 2010
Location: Brisbane
Posts: 10,584
Great work on the faint stuff, M&T

Cheers,
Rick.
Reply With Quote
  #6  
Old 19-10-2017, 03:47 PM
Atmos's Avatar
Atmos (Colin)
Ultimate Noob

Atmos is offline
 
Join Date: Aug 2011
Location: Melbourne
Posts: 6,980
Comparing all of the different versions... they’re all pretty awesome in their own rights
Very nice shot M&T
Reply With Quote
  #7  
Old 19-10-2017, 05:55 PM
Placidus (Mike and Trish)
Narrowing the band

Placidus is offline
 
Join Date: Mar 2011
Location: Euchareena, NSW
Posts: 3,719
Quote:
Originally Posted by Peter Ward View Post
Suspect the seeing let you down, but love the depth of the image.
Thanks Peter. Seeing was so bad on one night (about 3.5 sec arc) we gave up in disgust. It was blowing such a gale that we were worried about the structural integrity of the open flaps on the dome.

Quote:
Originally Posted by willik View Post
A little bit out of focus but still a very nice image not a easy target
Martin
Thanks Martin.

Quote:
Originally Posted by strongmanmike View Post
Great stuff guys, never before seen on IIS and now twice in under a month

Very interesting to compare our results actually, looking at the more diffuse extensions there is little or no difference in depth but as expected, the superior aperture has snuck just a little deeper on point sources...although, I don't apply decon to my star fields so there are probably some faint stars lurking in the background of my data?..I just hate spots in my background that you can't distinguish form stars. Comparing the detail in some surrounding galaxies I may just have had a little better seeing?.. oooor, we just used different processing approaches..? As you say, you look to have revealed some detail in the leading (left) edge of the main fan shaped tidal tail, which although subtle is indeed very cool. I am thinking from the look of the rest of the image, you used some solid extraction techniques here..? which is also cool, I love heavy extraction to go deep and reveal new things! ...image noise is overrated!

Overall another great use of a great instrument guys and great to see big high end equipment hitting interesting things, rather than the same ol samo

Mike
Confession: Trish was most impressed by your image, and strongly suggested that we have a go. Yours is clearly much sharper. Some of that is seeing. Some of it is perhaps that you have a superb instrument and we have a light bucket.

Quote:
Originally Posted by RickS View Post
Great work on the faint stuff, M&T

Cheers,
Rick.
Thanks Rick!

Quote:
Originally Posted by Atmos View Post
Comparing all of the different versions... they’re all pretty awesome in their own rights
Very nice shot M&T
Thanks, Colin. Perhaps we should have tackled this in the dead of Winter, when seeing tends to be better.

We suspect we're going to have to go off air very shortly. We suspect the seal on the camera chip chamber has failed, and we are getting ice crystals forming. Every night is worse than the night before.

Last edited by Placidus; 19-10-2017 at 06:33 PM.
Reply With Quote
  #8  
Old 19-10-2017, 06:21 PM
RickS's Avatar
RickS (Rick)
PI cult recruiter

RickS is offline
 
Join Date: Apr 2010
Location: Brisbane
Posts: 10,584
Quote:
Originally Posted by Placidus View Post
We suspect we're going to have to go off air very shortly. We suspect the seal on the camera chip chamber has failed, and we are getting ice crystals forming. Every night is worse than the night before.
My U16M has done that twice now. Class action?
Reply With Quote
  #9  
Old 19-10-2017, 07:08 PM
gregbradley's Avatar
gregbradley
Registered User

gregbradley is offline
 
Join Date: Feb 2006
Location: Sydney
Posts: 17,877
Fantastic image. Great to see such an interesting pair of galaxies imaged so well.

Greg.
Reply With Quote
  #10  
Old 20-10-2017, 07:40 AM
marc4darkskies's Avatar
marc4darkskies (Marcus)
Billions and Billions ...

marc4darkskies is offline
 
Join Date: Mar 2007
Location: Quialigo, NSW
Posts: 3,141
Yep, shame about your conditions but the depth is marvellous! Nice work.
Reply With Quote
  #11  
Old 20-10-2017, 08:10 AM
Stevec35 (Steve)
Registered User

Stevec35 is offline
 
Join Date: Aug 2010
Location: Canberra
Posts: 3,654
That's a nice deep image guys

Cheers

Steve
Reply With Quote
  #12  
Old 20-10-2017, 09:01 AM
multiweb's Avatar
multiweb (Marc)
ze frogginator

multiweb is offline
 
Join Date: Oct 2007
Location: Sydney
Posts: 22,060
Very deep Mike. Love the colours too.
Reply With Quote
  #13  
Old 22-10-2017, 08:37 AM
Placidus (Mike and Trish)
Narrowing the band

Placidus is offline
 
Join Date: Mar 2011
Location: Euchareena, NSW
Posts: 3,719
Quote:
Originally Posted by gregbradley View Post
Fantastic image. Great to see such an interesting pair of galaxies imaged so well.

Greg.
Thanks Greg.

Quote:
Originally Posted by marc4darkskies View Post
Yep, shame about your conditions but the depth is marvellous! Nice work.
Cheers, Marcus. We agonized about the one but were pleased by the other.

Quote:
Originally Posted by Stevec35 View Post
That's a nice deep image guys

Cheers

Steve
Thanks Steve.

Quote:
Originally Posted by multiweb View Post
Very deep Mike. Love the colours too.
Thanks Marc. We might have expected from the seeming vigor of the interactions that there would have been yet more intensely blue patches in the spiral arms, but it didn't want to come out that way.
Reply With Quote
  #14  
Old 22-10-2017, 01:19 PM
atalas's Avatar
atalas
Registered User

atalas is offline
 
Join Date: Mar 2005
Location: Sydney
Posts: 5,136
Nice shot guys.
Reply With Quote
Reply

Bookmarks

Thread Tools
Rate This Thread
Rate This Thread:

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 08:21 PM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Advertisement
Testar
Advertisement
Bintel
Advertisement