Go Back   IceInSpace > Images > Deep Space

Reply
 
Thread Tools Rate Thread
  #1  
Old 24-07-2015, 02:57 PM
jase (Jason)
Registered User

jase is offline
 
Join Date: Sep 2006
Location: Melbourne, Victoria
Posts: 3,916
M83 - Southern Pinwheel Galaxy

Hi All,

Time for change with some mainstream targets as opposed to obscure. This will be one of only a couple of galaxies I'll image with this set up I suspect. I don't mind how people slice and dice with image scale/sampling, galaxies need focal length for magnification and this rig simply hasn't got enough to do them justice. There are however a few reasonably sized galaxies worthy of imaging, perhaps not because of the detail within the galaxy itself but to display how far the galaxy extends.

Here's my rendition of M83

Processed in CCDstack, PI and PShop. Conventional L[HA+R]GB. This is not the prettiest of images as some of the data used was taken while the optical train was being worked on. Several of the subs looked reasonable so decided to use them. Not a large data set either but plenty of signal as one could expect with 16" of aperture operating at F/3.5 under the pristine dark skies of SSO. I am grateful of the support team at iTelescope SSO for putting up with my persistent annoyance in getting the optical train tuned. Corrector to CCD optical back focus requirements with the new Aspen CG16070 has been a challenge. Its now as close as I'll get it having mounted the filter wheel directly to the Aspen body so that the adapter plate is out of the path. There are likely a few more tweaks that could be performed but at this point I'm happy the system is finally producing results. There is an hour of Ha data using 900s subs to bring out the HII regions. I was quite impressed by how attractive this galaxy looks in Ha as such I've included an attachment displaying this emission line.

Cheers
Attached Thumbnails
Click for full-size image (M83iis.jpg)
196.4 KB122 views
Click for full-size image (M83-HA.jpg)
45.9 KB107 views
Reply With Quote
  #2  
Old 24-07-2015, 04:08 PM
codemonkey's Avatar
codemonkey (Lee)
Lee "Wormsy" Borsboom

codemonkey is offline
 
Join Date: Jul 2013
Location: Kilcoy, QLD
Posts: 2,058
Niiiiice... makes me wish I'd used my FR when I shot M83 recently. I think I actually prefer wider fields with galaxies. Good work!
Reply With Quote
  #3  
Old 24-07-2015, 04:12 PM
RickS's Avatar
RickS (Rick)
PI cult recruiter

RickS is offline
 
Join Date: Apr 2010
Location: Brisbane
Posts: 10,584
A very nice wide view of M83, Jase! Perhaps a longer integration with such a fast system and dark skies would pick up the star streams?

I was working on a long FL version of M83 when my camera packed it in

Cheers,
Rick.
Reply With Quote
  #4  
Old 24-07-2015, 04:23 PM
Rex's Avatar
Rex
Registered User

Rex is offline
 
Join Date: Jun 2010
Location: Townsville, Australia
Posts: 991
Spectacular Jase! Stunning clarity and lovely colours.
Reply With Quote
  #5  
Old 24-07-2015, 05:33 PM
jase (Jason)
Registered User

jase is offline
 
Join Date: Sep 2006
Location: Melbourne, Victoria
Posts: 3,916
Quote:
Originally Posted by codemonkey View Post
Niiiiice... makes me wish I'd used my FR when I shot M83 recently. I think I actually prefer wider fields with galaxies. Good work!
Cheers Lee! Some galaxies may suit a wider field. Most are distant and small in angular size so magnification is needed. Big chip imaging, you can have the best of both worlds or do a mosaic! Thanks for checking it out.

Quote:
Originally Posted by RickS View Post
A very nice wide view of M83, Jase! Perhaps a longer integration with such a fast system and dark skies would pick up the star streams?

I was working on a long FL version of M83 when my camera packed it in

Cheers,
Rick.
Thanks Rick! The stellar stream is certainly faint but not too difficult to capture with this system. I was able to see the arc in 40mins of clear filtered data. More integration may have delivered a smoother result but likely not brighter. There is a lot of information available about the M83 stream here - http://iopscience.iop.org/0004-637X/789/2/126/
Thanks for checking it out.

Quote:
Originally Posted by Rex View Post
Spectacular Jase! Stunning clarity and lovely colours.
Thanks Rex. Pleased you liked it. The background could have been flatter. I wasn't brave enough to go in with PI DBE or other tools. Due to differences in the camera angle throughout testing, some of subs didn't correct very well with flats. Seems to not have impacted the image too much.

Last edited by jase; 24-07-2015 at 06:03 PM. Reason: typo
Reply With Quote
  #6  
Old 24-07-2015, 05:41 PM
RobF's Avatar
RobF (Rob)
Mostly harmless...

RobF is offline
 
Join Date: Jul 2008
Location: Brisbane, Australia
Posts: 5,716
Nice going and thanks for sharing the Ha master. Very interesting in its own right, as you say.
Reply With Quote
  #7  
Old 24-07-2015, 05:55 PM
Regulus's Avatar
Regulus (Trevor)
Regulus - Couer de Leon

Regulus is offline
 
Join Date: Nov 2011
Location: Devonport, Tasmania
Posts: 2,350
That's a good result Jase, and it enlarged pretty good too Well done.

Trev
Reply With Quote
  #8  
Old 24-07-2015, 06:08 PM
jase (Jason)
Registered User

jase is offline
 
Join Date: Sep 2006
Location: Melbourne, Victoria
Posts: 3,916
Quote:
Originally Posted by RobF View Post
Nice going and thanks for sharing the Ha master. Very interesting in its own right, as you say.
Thanks Rob! Compared to many other galaxies, M83 has a substantial amount of Ha signal. Its certainly worth collecting data on it. Thanks for checking it out.

Quote:
Originally Posted by Regulus View Post
That's a good result Jase, and it enlarged pretty good too Well done.

Trev
Appreciated Trev! I'm pleased you liked it. A bit of fun to image mainstream targets for a change.
Reply With Quote
  #9  
Old 25-07-2015, 08:46 AM
strongmanmike's Avatar
strongmanmike (Michael)
Highest Observatory in Oz

strongmanmike is offline
 
Join Date: May 2006
Location: Canberra
Posts: 17,150
I think you are unnecessarily hard on your outfits capabilities, as this image shows and with that star stream showing up even in a short exposure, I think it could be a very useful galaxy shooter The other faint stuff you have there closer to M83's extremities, is all that real? It may well be but I can't find it in any deep shots including those in the link you supplied?

Lovely job

Mike
Reply With Quote
  #10  
Old 25-07-2015, 09:56 AM
jase (Jason)
Registered User

jase is offline
 
Join Date: Sep 2006
Location: Melbourne, Victoria
Posts: 3,916
Quote:
Originally Posted by strongmanmike View Post
I think you are unnecessarily hard on your outfits capabilities, as this image shows and with that star stream showing up even in a short exposure, I think it could be a very useful galaxy shooter The other faint stuff you have there closer to M83's extremities, is all that real? It may well be but I can't find it in any deep shots including those in the link you supplied?

Lovely job

Mike
Thanks Mike! Nah, 1400mm FL is too short to do significant damage on galaxies unless I'm seeking stuff like star streams and the like. No such thing as one instrument that can do it all, unless you've got a multi-focal length system like Rick's Ceravolo. I bought the 12.5" RCOS for galaxy work. Unfortunately I can't mount both ASA and RCOS on the PME simultaneously. With focal length, there is magnification and there is really no substitute for it.

The faint stuff near M83 real? I just photoshopped it in
Yes, it is real. I wouldn't present it if it wasn't in the data. Attached is the heavily stretched luminance with colour overlay for reference. Took some layer masks to present it correctly in the final result.
Attached Thumbnails
Click for full-size image (M83-extensions.jpg)
196.4 KB39 views
Reply With Quote
  #11  
Old 25-07-2015, 10:09 AM
strongmanmike's Avatar
strongmanmike (Michael)
Highest Observatory in Oz

strongmanmike is offline
 
Join Date: May 2006
Location: Canberra
Posts: 17,150
Oh well, image scale is image scale...each to there own re imaging galaxies

Regarding the faint stuff, I didn't think you PS'd it in was just wondering if it was some very vague processing left over or not. I noted it in your LRGB (with some excitement mind you) so pulled it into Astroart5 and applied a Guassian stretch (which is great at showing up the faint stuff in the frame in one click) to your full frame image and it doesn't look like that B&W stretched image you have posted there Just interested because I haven't seen that stuff before so if you have revealed something new lets showcase it .

Mike
Reply With Quote
  #12  
Old 25-07-2015, 10:11 AM
alpal's Avatar
alpal
Registered User

alpal is offline
 
Join Date: Jan 2012
Location: Melbourne
Posts: 3,602
Nice work Jason,
I never realised that M83 was so big.
It's 9 times larger than I thought.

cheers
Allan
Reply With Quote
  #13  
Old 25-07-2015, 10:30 AM
jase (Jason)
Registered User

jase is offline
 
Join Date: Sep 2006
Location: Melbourne, Victoria
Posts: 3,916
Quote:
Originally Posted by strongmanmike View Post
Oh well, image scale is image scale...each to there own re imaging galaxies

Regarding the faint stuff, I didn't think you PS'd it in was just wondering if it was some very vague processing left over or not. I noted it in your LRGB (with some excitement mind you) so pulled it into Astroart5 and applied a Guassian stretch (which is great at showing up the faint stuff in the frame in one click) to your full frame image and it doesn't look like that B&W stretched image you have posted there Just interested because I haven't seen that stuff before so if you have revealed something new lets showcase it .

Mike
Well its the same data Mike so the only thing I can think of is the mask blurring has caused the effect you see. I'll check the RGB data as well to be sure. I don't think its anything new to showcase. I've seen a few images showing the extent of the galaxy around.

Quote:
Originally Posted by alpal View Post
Nice work Jason,
I never realised that M83 was so big.
It's 9 times larger than I thought.

cheers
Allan
Thanks Allan! It has some faint structure to it which we can now call M83. No idea what the designation was of the galaxy it previously consumed!
Reply With Quote
  #14  
Old 25-07-2015, 10:39 AM
strongmanmike's Avatar
strongmanmike (Michael)
Highest Observatory in Oz

strongmanmike is offline
 
Join Date: May 2006
Location: Canberra
Posts: 17,150
Quote:
Originally Posted by jase View Post
Well its the same data Mike so the only thing I can think of is the mask blurring has caused the effect you see. I'll check the RGB data as well to be sure. I don't think its anything new to showcase. I've seen a few images showing the extent of the galaxy around.
In the LRGB, although rather faint, there are several distinct faint features/arcs in the general area between the outer stream arc and the galaxy as well as on the other side of the galaxy above and right, these are not present in your B&W stretched version..? When the LRGB is guassian stretched there is a complete ring of faint material, have a go you'll see it. Extreme stretching a final LRGB will of course show up all the warts and I get that, who cares, I was only doing it to see what these seemingly new features I could see in the LRGB might be.

Please understand, none of this rather extreme manipulation is intended to detract one iota from what is an excellent image of M83 as presented (and the way it was intended to be viewed), I love looking for faint features, heck I have found my share of faint jets and vague extension no one else can see and you have the prefect instrument and imaging location to find them!

Mike
Reply With Quote
  #15  
Old 25-07-2015, 12:58 PM
rustigsmed's Avatar
rustigsmed (Russell)
Registered User

rustigsmed is offline
 
Join Date: Mar 2012
Location: Mornington Peninsula, Australia
Posts: 3,950
very nice work Jason. some great resolution despite the FL esp in Ha. looking forward to seeing more from your new scope.

Cheers

Russell
Reply With Quote
  #16  
Old 25-07-2015, 02:00 PM
gregbradley's Avatar
gregbradley
Registered User

gregbradley is offline
 
Join Date: Feb 2006
Location: Sydney
Posts: 17,877
Now we're talking Jase.
Your 16070 leaves that 16000 for dead.
Backgound shows nice contrast star colours are great. A look I now associate with the 16070 and I like it.

Your M83 is very good and perhaps as you say a bit more detail is available with focal length. But I agree with Mike about not writing off your setup for galaxies.

Its an interesting question as to whether there is any real difference between imaging at long focal length and imaging at shorter focal length and cropping with the same aperture.

Greg
Reply With Quote
  #17  
Old 25-07-2015, 06:01 PM
jase (Jason)
Registered User

jase is offline
 
Join Date: Sep 2006
Location: Melbourne, Victoria
Posts: 3,916
Quote:
Originally Posted by strongmanmike View Post
In the LRGB, although rather faint, there are several distinct faint features/arcs in the general area between the outer stream arc and the galaxy as well as on the other side of the galaxy above and right, these are not present in your B&W stretched version..? When the LRGB is guassian stretched there is a complete ring of faint material, have a go you'll see it. Extreme stretching a final LRGB will of course show up all the warts and I get that, who cares, I was only doing it to see what these seemingly new features I could see in the LRGB might be.

Please understand, none of this rather extreme manipulation is intended to detract one iota from what is an excellent image of M83 as presented (and the way it was intended to be viewed), I love looking for faint features, heck I have found my share of faint jets and vague extension no one else can see and you have the prefect instrument and imaging location to find them!

Mike
Hey Mike! yes I evaluated the differences between the LHaRGB and stretched luminance and found the culprit mask that had not been correctly blurred. I've just uploaded a 'corrected' version. Still has the faint galactic extension and star stream. I also took the opportunity to flatten the background in this new version which appears to have slightly brightened it? and I didn't bother with noise reduction. Oh well...No more repros on this data set. It was test data to start with while the image train was being worked on but I was itching to process something. Thanks for the input. Appreciated.

Quote:
Originally Posted by rustigsmed View Post
very nice work Jason. some great resolution despite the FL esp in Ha. looking forward to seeing more from your new scope.

Cheers

Russell
Thanks Russ! M83 has been well placed the last few weeks. Crosses the meridian early in the evening so I was able to get most of the data at zenith. I did throw out quite some data due to shotty guiding where by post camera and OAG rotation, I didn't both recalibrating etc. Scope is unchanged as I've posted images from it before, the only new item is the Apogee Aspen CG16070 which I believe is a good match for this set up.

Quote:
Originally Posted by gregbradley View Post
Now we're talking Jase.
Your 16070 leaves that 16000 for dead.
Backgound shows nice contrast star colours are great. A look I now associate with the 16070 and I like it.

Your M83 is very good and perhaps as you say a bit more detail is available with focal length. But I agree with Mike about not writing off your setup for galaxies.

Its an interesting question as to whether there is any real difference between imaging at long focal length and imaging at shorter focal length and cropping with the same aperture.

Greg
Cheers Greg! Yes, the KAI-16070 is certainly a winner over the KAI-16000. I actually didn't mind using KAI-16000 but the results are better with the KAI-16070 due to its improved well depth. I also requested a class 1 sensor so its very clean. I will consider imaging a couple more galaxies but no promises.

Last edited by jase; 25-07-2015 at 07:15 PM. Reason: typo
Reply With Quote
  #18  
Old 26-07-2015, 10:03 AM
tilbrook@rbe.ne's Avatar
tilbrook@rbe.ne (Justin Tilbrook)
JHT

tilbrook@rbe.ne is offline
 
Join Date: Jun 2007
Location: Penwortham
Posts: 3,039
Interesting and inspiring image Jase!

Regardless of the problems it's amazing to see some hint of the star streams plus all the other faint background galaxies.

Cheers,

Justin.
Reply With Quote
  #19  
Old 27-07-2015, 04:29 PM
jase (Jason)
Registered User

jase is offline
 
Join Date: Sep 2006
Location: Melbourne, Victoria
Posts: 3,916
Quote:
Originally Posted by tilbrook@rbe.ne View Post
Interesting and inspiring image Jase!

Regardless of the problems it's amazing to see some hint of the star streams plus all the other faint background galaxies.

Cheers,

Justin.
Thanks Justin. Yes, background galaxies are plentiful that's for sure. My favourite are the two top right of the frame. There are some far fainter ones present too which are easily mistaken for stars. Thanks for checking it out.
Reply With Quote
  #20  
Old 27-07-2015, 06:44 PM
RobC (Rob)
Registered User

RobC is offline
 
Join Date: Apr 2012
Location: Woodford , Queensland , Australia
Posts: 218
Jase - Fantastic rendition , top marks. Agree with you and would like to see you treble your focal length. Buggered if I can work out or locate those fuzzies Mike is talking about.

Rob
Reply With Quote
Reply

Bookmarks

Tags
16" asa, m83

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 03:36 AM.

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