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jase
15-08-2011, 08:59 PM
Hi All,

I imaged this while finishing off other targets in the earlier hours. Thought the scene would be interesting given the object pairing of a globular and spiral galaxy. Looks like two coins as opposed to the single Silver Coin galaxy. Ironically, the Silver Coin galaxy doesn't look that silver either, more like corroded copper coin...

Two Silver Coins (http://cosmicphotos.com/gallery/image.php?fld_image_id=234&fld_album_id=12)

Located in the constellation Sculptor, the Globular cluster NGC288 (top left) and at 1.8 degrees south-east the spiral galaxy NGC253 (aka Silver Coin galaxy) appear to interact. However, they are in fact extremely far away from each other. NGC253 was discovered by Caroline Herschel in 1793 and is one of the brightest galaxies beyond our local group. Both objects are near the South Galactic Pole, a point on the celestial sphere that is not obscured by stars and gas as it is at right angles to the Milky Way. Due to this a rich field of galaxies both bright and dim are visible across the presented scene. NGC288 is approximately 30,000 light years away, while NGC253 is 10 million light years away hence there is no interaction between them.

Well, being a single frame image, I though I'd try process this image entirely in PixInsight. eeekkkk! Way out of the knowledge zone. Overall I think its a reasonable job. Not certain what happened to the star alignment function as it looks like far edges of the frame aren't aligned - perhaps the data was the cause. I will be honest, I don't like the data rejection routines in PI. They work, don't get me wrong but there's a lot of fuzzing around getting the right balance. I'm sure I would become more proficient at it, but CCDStack still feels superior. I love the ability to see what you are rejecting as opposed to throwing your subs into an outlier rejection algorithm and repeating the result again and again until you are satisfied all you are throwing out is outliers as opposed to important data. DBE on the other hand - it rocks on simple scenes like this! Was quite impressed. I intentionally stretched the data hard to bring out the full shell of NGC253. The shell itself extends further than I expected and with an interesting lobe. Plentiful background galaxies both bright and dim are present. I experimented with DDP to get the stellar profiles right but it took two hours to understand how to integrated them again with masks. All part of the learning curve I guess. I don't think I'll be doing that again! HDR Wavelet Transform processing is still to be discovered. One step at a time but I'm enjoying it. I'm keen to see how well PI handles Ha+R combines and the like. In all seriousness, I can see myself swapping data in and out of various tools. I have more data to process so will try the hybrid approach when I get a chance. PI seems to mangle the FITS data when bring it back into CCDStack. Seems there are differences in 32 bit float point formats - more to learn.

Anyway, thanks for checking it out.

Cheers

Paul Haese
15-08-2011, 09:17 PM
Actually quite nice Jase. Huge field of view and I like the composition too.

edit. I know nothing about PI but I do like CCDstack myself and I think I will stick with that.

Ross G
15-08-2011, 09:18 PM
A great photo Jase.

I love the contrast of objects and colours.


Thanks.


Ross.

Peter Ward
15-08-2011, 09:28 PM
I'm a little set in my ways....for example, much of the stuff on the radio, and now the web, to me just has that "muzak" drone to it....

Then, occasionally, one of my favorite bands gets some air play....

....and is a literally a breath of fresh air. Stones. Van Halen. Fab-four. Led Zep. Steely Dan... Unforgettable riffs, vitruiosity & musicianship.

And so it is with pictures from your well honed imaging gear Jase.....

Nice one :thumbsup::thumbsup:

jjjnettie
15-08-2011, 09:44 PM
Beaut stuff jase.

jase
15-08-2011, 09:45 PM
Cheers Paul. I didn't think too much on the composition with this one. Just a quick scan to realise it would fit in the FOV nicely!

Stick to what you know if you're comfortable with how it manipulates your data. I'm only trying the PI route to get a feel for the software capabilities. I don't think I'll make the switch but will look to leverage off certain routines in the package to improve output quality. I think the challenge in learning a new processing package is understanding the workflow differences, then getting a detailed look under the hood on how algorithms work on the data. The latter is a challenge if the software is not well documented, which is the case for some of the PI components. Trial and error is one thing, but to have a solid understand of an algorithm and making the most of it is a different ball game. Thanks for the feedback.



Thanks Ross. The object pairing make from something different. Pleased you enjoyed it!



Cheers Peter. I hear you. Mainstream 'musak' has its place. Once must not become too complacent. Though its not easy. Thanks for checking it out!



Thanks JJJ! :)

gregbradley
15-08-2011, 09:47 PM
A fresh look Jase.

I'm experimenting on and off with PI as well. So that is good to hear your view of it so far.

I need to watch the video tutorials. So far the mosaic tools seem best.
I am yet to see a gain on the other types of tools but not too early for me to tell really.

Greg.

Ric
16-08-2011, 12:04 AM
A wonderful image Jase.

What an amazing field of view you have with that camera.

midnight
16-08-2011, 12:14 AM
One word - Beautiful!

Darrin...

SkyViking
16-08-2011, 06:17 AM
A very beautiful view there Jase. That's an excellent pairing of objects, and the background is littered with far-away galaxies too. Thanks for sharing :)

atalas
16-08-2011, 06:55 AM
Great seeing these too together,and isn't that shell cool! top stuff Jase.

leon
16-08-2011, 08:18 AM
Beautiful capture Jase, I remember doing this region myself once, and I have to admit it came out pretty good for someone with my experience, which was not that much at the time.

Have to say yours dose stands out beautifully with colour, and the crisp and clean appearance, top image Jase, You guys are just so good at this stuff.

Leon

RB
16-08-2011, 08:30 AM
Beautiful FOV and masterfully well resolved with fantastic colour definition !

Onya Jase.

:thumbsup:

JohnG
16-08-2011, 09:14 AM
Hi Jase

A lovely FOV, huge expanse of sky you have there, interesting to see both those objects in context.

Like others, I think I will stick with what I know :).

Cheers

strongmanmike
16-08-2011, 09:20 AM
Interesting composition Jase, the outer halo of NGC 253 is not seen in images that often so all-round nice work :thumbsup:

Mike

alexch
16-08-2011, 10:11 AM
What a beautiful image!!!

jase
16-08-2011, 11:46 AM
Sounds good Greg. Never hurts to try something different. It took me a few goes with PI on this data set. The mosaic feature sets are quite strong, especially the latest process 'GradientsMergeMosaic'. I've not pushed entered into this yet but it would appear to be promising. That said I'm always cautious of automated work flows until I understand what its doing to the data. You don't want to sacrifice the fidelity of luminosity such as suppressing highlights to match all frames. There needs to be a good balance. Manual panel matching can be tedious alas still provide the most flexibility. More experimenting will tell.



Cheers Ric. Yes, 239 arcmin square with the Apogee U16M. Provides plenty of imaging real-estate!



Pleased you enjoyed it Darrin! Thanks!



Thanks Rolf. I find object pairings interesting purely in a spacial distance sense. So close, yet so far. This area is cluttered with background galaxies. Thanks for your comment.



Thanks Louie. Yes, the outer extension of 253 is interesting. I used 20min lum subs so plenty of depth to bring it out. I didn't realise how far it extended. Always something new and surprising. Thanks again.



Cheers Leon. Yes, your comment has jolted my memory. I recall you imaged this a while back. It provides for a great scene that's for sure. Thanks for the feedback.



Thanks RB. Still learning the ropes when it comes to handling colour in PI. This one seems to work ok. Thanks for check it out.



Cheers John. The pairing is something different. Couldn't agree more with sticking with what you know. Half the battle in processing is to know what to do and when. Adding another tool into the mix that has a different work flow complicates things but I look at it as being well rounded. I open to new concepts that will push data to greater heights. I appreciate the feedback.



Thanks Mike! No much in the way of framing/composition logic was used here. I'd normally spend considerable time on planning but this was simply a fill in object of the pre-dawn hours. Pleased you liked the scene.



Thanks Alex!

strongmanmike
16-08-2011, 12:14 PM
5.5hrs = a fill-in, you kidding? That's a whole night for me :lol:...I assume you had the crimson beauty point your gear there for a bit each morning over a few nights..?

Mike

jase
16-08-2011, 12:46 PM
Yep. Over a few mornings Mike. Am trying to optimise the set up so that I can squeeze as much imaging time as possible between the start and end of astronomical twilight where civil twilight is spent taking flats. I'm getting close to hitting 8.5 hours on a full clear night - nirvana. I should be able to get a bit more out of it but need to factor in regular auto focus periods, plate solves and guide star acquisition/settling. This all assumes the weather cooperates, otherwise I get what I can take. The basis is if its clear, I'm imaging.

strongmanmike
16-08-2011, 02:41 PM
Wow 8.5 hrs - that's productive! Is that all imaging time?

I managed nearly 21hrs (plus flats time) over 3 nights in May 08 for my Deep Cen A and I thought that was good :eyepop:...The manual focusing, meriadian flips and re-framing etc eat up time (multiple targets would have been much more time consuming). Apart from the odd stroll to talk with other astronomrs and a few 30min kips here and there, I was out with the scope the whole time too :lol: :screwy:

My recent fighting dragons image was another 6.5hr 6 filter (plus flats) deep image in one night...but sheesh, it is a challenge...I envy your obs and PME :sadeyes: :thumbsup:

Mike

Stevec35
16-08-2011, 04:05 PM
Nicely done as usual Jase. I did this field myself once many years ago but it didn't look nearly as good as yours. Although I have Pixinsight I don't use it much. I might if they ever wrote a manual.

Cheers

Steve

FlashDrive
16-08-2011, 07:32 PM
Jase ... that's Awesome ... nice wide field shot also and beautiful colour.

Flash

CoolhandJo
16-08-2011, 07:43 PM
Like space walking! Awesome.

Lester
16-08-2011, 08:40 PM
Beautiful Jase, thanks for the view.

multiweb
17-08-2011, 06:04 PM
Never seen this one in a wider field. Interesting composition. :thumbsup:

glenc
18-08-2011, 04:33 PM
Great image Jase. All of your images are amazing.
I think NGC 253 should be called Caroline's galaxy because she found it.

jase
19-08-2011, 12:14 AM
Yes Mike. Some data is scrapped due to undetected high level clouds or similar. I kid you not that its taken more time setting up the software than the hardware. Its finally rock solid hence very productive.



Thanks Steve. Its a pleasant yet diverse object pairing. PI has mouse over details so you can read up on what certain buttons, sliders and setting do. Their forum is pretty good for obtaining information too. Like all processing software, if you spend the time to learn it, you'll get solid results. Thanks again for checking out the image.



Cheers Colin. Pretty hard to get solid details in NGC253 at this focal length but PI wavelet functions didn't do a bad job.



Cheers Paul!



Thanks Lester!



Cheers Marc. The two targets do provide for an interesting view.



Thank you kindly Glen. Appreciate the positive feedback.

===
Thanks all :D