Centaurus A Ultra Deep Field

[strongmanmike]

Here is a unique and very deep view of this famous galaxy in Centaurus.

Taken over 3 nights from a very dark sky this may even be the deepest colour image ever taken of this famous galaxy..?

The following link is to a 1400 X 900 image that will fit on most screens without the need for scrolling but please access a larger file and several other versions of this extensive data set via the links below the image (don't click on the image)

I strongly recomend looking at the 4008 X 2670pix 4.5meg version and see how many galaxies you can count in the background.

The close up of the dust lane is pretty cool too I recon.

A real pleasure to process into so many variations, I hope you like it :thumbsup:

http://www.pbase.com/strongmanmike2002/image/97061387/original

Mike

[jase]

YEAH! :thumbsup::thumbsup: Top shelf to the core there Mike. Love the full size version. Background galaxies are plentiful and the halo extension is impressive. Natural and elegant image processing. A question though, what did you do about background colour noise reduction...I think you could have been harder in this processing task. Don't get me wrong, there isn't much background colour noise about, but I noticed it in the fainter edge regions of the halo. Well done. CWAS?:D

[Peter Ward]

Yes, technically commendable, but aesthetically...hummm...I went there with my own data, and decided not to run with it...that said...looks nicely done with the starfire!

[AlexN]

That 4mb image is INCREDIBLE! Very interesting looking background galaxy in the top right, and Centaurus A Is stunningly bright and vivid..

Job well done.

[iceman]

Wow Mike, that's a stunning result. Well done. The trip to Ilford was worth it!

[Lester]

Eye catching deep image, fantastic Mike.

[Hagar]

Lovely detailed image Mike. I dont think I will spend the rest of the day counting the galaxies in the background. The dust lane is beutifully in focus and quite stunning in it's soft detail.. ( Idon't mean soft I really mean delicate). I guess this would have been a dificult one to process. Can you give us some idea of your processing routine for a large set of frames like this?

[strongmanmike]

Ah, there's that Eagle eye of yours again :doh:what would we mere imperfect mortals do without you Jase? :rolleyes:

A: I didn't do anything about the background noise, that's the raw simple (ie non Jase like) processing result - I had excellent data from an excellent site with an excellent camera, pretty simple....aaaand it doesn't show in a big glossy 20" X 16" print either :D

Glad you liked it even with that aweful colour din :rockband: :lol:

Mike

[h0ughy]

Well done Mr Sidonio, can almost hear the corks popping on this one!!

[jase]

:lol: Eagle eyes :lol: Nope just a quality calibrated monitor set up in room with low ambient light, but it helps to know what to look for. Seriously though, I scrutinise your images just as I do my own. Perfection does not exist, yet we still strive for it. You've got to have goals. While I hear you loud and clear - "excellent data from an excellent site with an excellent camera", you're still fooling yourself if you don't think you need noise control mechanisms in place.

Double the amount of data you've acquired and you'll still need to manage it. The reason being is what you are dealing with is not directly noise related to the quality of the data, but the image processing routine itself. Certain tasks are best performed at different times to minimise introducing noise into the image. A classic example is a bad deconvolution PSF model. If the selected star less than ideal, it will wreck havoc on the image. You may not notice the result immediately, which is to be expected - When you run deconvolution you're analysing how the stars have tightened up and other details such as nebulosity are taking form. These are the positives, but you've also got to evaluate the negatives such as noise or the loss of nebulosity due to the deconvolution process. Hence my tip would be to blink your raw and deconvoluted images while examining them thoroughly. This will give you a clear indication of the positives and negatives. Typically the negatives can be dealt with.

It comes as no surprise that the image looks great on print. Printers are much less discerning compared to a monitor - we are only talking about 300dpi and considerable gamut differences here. Be prepared to pay big bucks for your prints if you want the "goods".

Don't get me wrong Mike, this is a "Grade A" image and certainly shows the equipment capabilities along with the operators skill. It is nothing short of excellent work. Sometimes we get overly caught up in processing that we overlook the basics. Once again, well done.:thumbsup::)

[Bassnut]

Very nice Mike, lots of sharp detail there even zoomed in, and sure is deep :thumbsup:

[Tamtarn]

That is really deep Mike. Great detail and very subtly processed.

[Ric]

Fantastic Mike, A real stunner.

Cheers

[skeltz]

Well thats a real rip snorter mike,kudos.
Well worth the effort and many cups of coffee i Imagen:cool::cool::cool:

[Alchemy]

Another big effort there mike, will have to spend some time looking through the images. good to see you out of the city and enjoying yourself.


As for the Jase he will post another image soon and it will be your turn:gamer:

[seeker372011]

fantastic image..its certainly worth having a look at the 4 meg download ..it certainly is aunique view of a familiar object

[strongmanmike]

I like simple real cooking, each to their own as they say, thanks for the advice though...daddy :hi:

Mike :)

[Screwdriverone]

Phew, I just extracted myself out of the deep field 4 meg image after counting up all the cool little dotted and curved groups of stars and got so far into it, I almost fell in.

My conclusion?

Holy Cow!

Chris.

[strongmanmike]

Glad you enjoyed it and yes it came out pretty bright in the end, as I watched it acumulate over the 3 days at Wiruna I got more and more excited :)



Sure was Mike, never done anything like that before - a 3 day trip to image one object :screwy:



Cheers Lester



Cheers heaps Doug! My processing rotine is a very basic but in a nut shell, I align and combine, then DDP and log stretch and finally LRGB combine in Astroart4, then I pull it into photoshop and play with levels, curves and sharpening...a no brainer really :shrug:..ok a little more is involved like layering and blending (much of which is processing on the run by gut feeling) but that's about it :)



:lol: dunno about that Dave :rolleyes: but I think that means you enjoyed the image..?



Cheers Fred, I thought these two latest images would gain me browny points from you, given they are such long exposures ;). Sorry they are still too wide field for ya though :)



Cheers Dave and Barb (which of you is writing this?) and I guess that was what I was hoping for, I went into this with an open slate as to what I would get, the result was more than pleasing.



Glad you think so Ric!



Yes lots of coffee Rob! Generally I would start a 60min imaging run then pop off to the camp kitchen at Wiruna and enjoy the fire, coffee, wine and a chat until the lame woosy people left and then it were only me each time I came back for more :(.....The whole three days went without a hitch, everything went perfectly, weather, equipment and the location not to mention the people :thumbsup:



I have really enjoyed looking at the various versions myself actually! I've spent hours scanning the images particularly the big "Deep Field" file and the amount of background galaxies is staggering :eyepop:. You can even make out the optical component of the blackhole jet and many globular clusters in the halo.

As for Jase...? Ahh he means well, just doesn't realise he can sound a bit huberistic, pedantic and patronising at times but I forgive him :thumbsup:



Cheers Narayan, I wanted to present Cen A in a way (ways) never before seen :D



Yes indeed Chris, the background galaxies (and globular clusters in the halo) are pretty incredible huh?

Thanks

[tornado33]

Ive never ever seen such a deep image of this region. Many moons ago I read the Malin book "colours of the stars" where he showed a deep monochrome negative of it. But it wasnt so deep to show the galactic cirrus. This might well be the deepest ever image of the NGC 5128 area. Indeed the lobes from the black hole jet are easily seen. If it is possible to measure the surface brightness of the faint cirrus, or the lobes, I wonder what it would be? very very faint no doubt.

If youre looking to go this deep again, try the Chamelion Nebula complex, theres lots of integrated flux nebulae, dark and reflection nebula to be caught.

I think your imagery here is among the deepest ever seen. Some questions if I may :)
how did you power your scope? do they have 240V there?
Did you do 10 minute subs, or longer under the darker sky?
Thanks so much for sharing this amazing imagery
Scott

[strongmanmike]

Well, I am chuffed that you enjoyed it so much Scott :)

Did you have a look at all the versions on my site? I presented the data set in several different ways to showcase different aspects.

Yes going super deep was my intention mate and I knew to really bring out the faint galactic cirrus in the region would take very dark skies so Wirruna it was :D

I used 240V mains from the main lecture hall and yes I still used 10min subs to reduce the chance of losing too much data should something go wrong in a sub. As it turned out I only ended up with 4 or 5 bad subs out of 120 or so. Going onger would have been better of course but I had to weight it up I guess?

Cheers

[Terry B]

Stunning result.
How do you combine the subframes?
Are they averaged or added in some way?

Also it would be very interesting to add some radio data to this image in a similar way to this image (http://antwrp.gsfc.nasa.gov/apod/ap020812.html).

[strongmanmike]

Hi Terry

First of all, I am really glad you enjoyed the image, I hope it is something unique for many people, it was for me.

Yes I perused many images of Cen A both before and after my project. One thing I was looking for was radio data that matched the outer polar extensions that show up clearly in my image. The only ones I could find showed the more famous radio lobes that correspond with the inner jets..? Anyone help..?

You can see the optical component of the core jet though as a blue streak pointing at about 2.30 on the clock face above right of the bright core, about where most images would show the halo finishing.

I used 10min sub frames at -35C with my FLI ProLine CCD camera and added or "summed" them (not median or average) using Astroart4 image processing/camera control software. Astroart is excellent software and the only such software I have used now for coming up to 5 years, since I started CCD imaging!

Cheers again

Mike

[tornado33]

Yes I looked through all the images. The enhanced luminance and negative view are amazing. Its quite amazing that when you go to a very dark site, interstellar space would be far darker as theres no air glow, just the feeble light of the distant stars, yet you pick up gas and dust lit by that feeble light.

yes summing the data is the go as the more subs you add the deeper the image goes.

technically one could do such deep images with remote telescopes at dark skies but by gee the telescope time would be costly.
Its handy your setup is portable!

I guess you will be keen to locate other areas of the sky that would show interesting things when imaged so deeply. Perhaps there may even be some areas of faint nebulosity yet to be discovered :)
Scott

EDIT:. Mike youve recorded a blue arc of stars (http://antwrp.gsfc.nasa.gov/apod/image/0210/cena_peng_arrows.jpg). I can just see it on your big image here (http://www.pbase.com/strongmanmike2002/image/97573250/original) Main article here (http://antwrp.gsfc.nasa.gov/apod/ap021017.html)

[Terry B]

Thanks for the info. I thought that you must have summed the data to get such depth.
I had a quick search for the 21cm data but didn't come up with much. Short of requesting the data set from the ATCA and reducing it I don't have an easy answer.

[strongmanmike]

Yes true dark skies are now going to be hard to ignore for my imaging :doh:

Yes you are correct that blue arc of stars is indeed visible as is teh main jet on the other side. I had to use averted vision for the blue arc you mention and turn my head on the side but it is deffinitely there, I can make out the fainter thicker shell below it closer to the centre of the galaxy in fact. I did try the deconvolution filter in Astroart that is supposed to reveal these arcs when I was preparing my DM entries but I couldn't get it to work properly :shrug:

Thanks again

Mike

[ngcles]

Hi Mike and all,

Firstly Mike, congratulations on the image it is simply superb -- loved it.

Tornado wrote:

"But it wasnt so deep to show the galactic cirrus. This might well be the deepest ever image of the NGC 5128 area."

It is a very very deep image but David Malin (using a slightly larger telescope it has to be said) has gone deeper and it is crazy -- wild. See attached.

[strongmanmike]

Well, it's hard to say unequivically that David's image is deeper..? It is certainly a wider field but my negative data shows pretty much everything in Davids shot is in mine too.

http://www.pbase.com/strongmanmike2002/image/97429465/original

I could have pushed this negative image further but I was trying to maintain a natural dynamic range even in the negative that showed the inner details as well as the faint outer stuff. When I pushed the negative data there is bloody heaps of Cirrus in there I can tell you.

To see just how deep my colour Ultra Deep Field version is and although enhanced somewhat, this is pretty much that image desaturated in Photoshop:

http://www.pbase.com/strongmanmike2002/image/97429117/original

If you crop Davids image to match mine I have revealed it all aaand still managed to maintian some detail in the core :D

Davids shot was just about a 70 to 90min exposure I think?...buuuut with a 1.2m aperture F2.5 telescope/camera, the UK Schmidt of course. David had to use his amazing image amplification techniques to bring out the very faint details but in the process this analogue technique lost all the inner details altogether and this is what I was trying to avoid with my modern digital techniques.

I think Scott is right though, I cannot find a deeper "colour" image that shows the entire expanse of Centaurus A with preserved inner details "and" showing the surrounding faint Cirrus..?

Centaurus A has been imaged many many times by many many people so who would have thought that it was possible to still produce a unique image of it :). It was a truly exciting project for me and I hope it has inspired others to attempt similar ones :thumbsup:

Mike

[Ian Robinson]

Super .... amazing how far the halo of that galaxy extends .... the detail in the equatorial dust is great too.

[netwolf]

Very nice details and i think its deepest of this field i have seen. Also like the Saturn look alike ghost that you can almost make out.

[tornado33]

It seems the only limiting factor in these images is the stars themselves, as even the faintest of stars are revealed in puching the magnitude limit back so far. I look foward to many more such deep images from you Mike, though they require so much imaging time to do :)
Scott

[strongmanmike]

I like the negative image becasue it really emphisises the subtle overlapping faint shells in the huge outer halo.



Yes it would be nice to measure the limiting star magnitude in this image, the cirrus nebulosity is fainter than 25 mag/square arc sec, so who knows? :)

It is clear that you have enjoyed these images Scott and that makes me pretty happy mate :thumbsup:

Mike