Antlia Galaxy Cluster (Abell S0636) - Extreme Deep Field - 152 Hours

[SkyViking]

Hi All,

It has been a while since I posted a new image, but hopefully this one will make up for it :)

With 152 hours taken over 55 clear nights (January to June 2015) here is finally my latest 'extreme deep field', this time showcasing the mighty (and rarely imaged) Antlia Galaxy Cluster (Abell S0636).
This is likely one of the deepest ground based images ever taken by either amateur or professional telescopes and the faint Intracluster Light visible between the two subgroups doesn't seem to be described in literature.

It has been a humbling experience to gather and process all this data. When I embarked on this project I specifically wanted to obtain a very deep view of a galaxy cluster, but I certainly did not expect to uncover such a treasure trove of features in this one little patch of sky. The entire image seems to be bursting with action, ranging from the varied and colourful cluster members themselves to obscure ultra-faint dwarf galaxies, Intracluster Light and Integrated Flux Nebula, red filaments from an ancient supernova remnant and a generous number of deeply reddened extremely distant galaxy clusters littered across in the background.
The H-Alpha filaments were a nice surprise for me. I was oblivious to their existence until very late in the process when some extremely faint streaks began to show up in test stacks. But after I grabbed an extra 8 hours of 2x2 binned H-Alpha data they came up nicely and I think they add a beautiful touch to the final result.

Link to full resolution image (4MB) (http://www.rolfolsenastrophotography.com/Astrophotography/Antlia-Galaxy-Cluster/i-3GJdqqH/O)
Link to medium size image (http://www.rolfolsenastrophotography.com/Astrophotography/Antlia-Galaxy-Cluster/i-3GJdqqH/X3)

Supplementary views:
Annotated Image (http://www.rolfolsenastrophotography.com/Astrophotography/Antlia-Galaxy-Cluster/i-vdHZvP5/A)
Comparison with DSS and GALEX fields (http://www.rolfolsenastrophotography.com/Astrophotography/Antlia-Galaxy-Cluster/i-MCLcGHZ/A)
Luminance Stacking Progress, 0 to 103 hours (http://www.rolfolsenastrophotography.com/Astrophotography/Antlia-Galaxy-Cluster/i-Sb22cmT/A)
Contour Plot of IcL and IFN Light (http://www.rolfolsenastrophotography.com/Astrophotography/Antlia-Galaxy-Cluster/i-DTnHd7C/A)
Micro Dust Cloud Superimposed on top of NGC3269 (http://www.rolfolsenastrophotography.com/Astrophotography/Antlia-Galaxy-Cluster/i-fgcM3NZ/A)

The Antlia Galaxy Cluster
The Antlia Cluster (Abell S0636) is a compact cluster of galaxies located in the Southern constellation Antlia (The Air Pump). It forms part of the large Hydra-Centaurus Supercluster and lies some 133 million light years distant, which makes it possibly the third closest galaxy cluster to our Local Group, after the the Virgo and Fornax Clusters.
The cluster contains around 234 galaxies and is unusual in that it does not have a single dominating brightest member. Instead its member galaxies are split into two subgroups, with the Northern (bottom centre) subgroup concentrating around giant elliptical galaxy NGC 3268 and the Southern (upper left) subgroup around another giant elliptical, NGC 3258.
The cluster is very compact compared to other similar clusters and contains a large number of early-type ellipticals and lenticulars, including several rare compact dwarf ellipticals. This ultra-deep image reveals that many of these galaxies are gravitationally interacting to some extent; faint tidal tails and distorted haloes are common throughout the field of view. In fact, the only large galaxy which presents an undisturbed classical spiral structure is the beautifully shaped PGC31094 near the right edge.
A vast number of smaller background galaxies are visible everywhere in the image. Many of these appear grouped into distant clusters of their own, far beyond the realms of the Antlia Cluster itself.

Extended Halos of the Giant Elliptical Galaxies
The large extended halos of the giant ellipticals NGC3268 and NGC3258 are very prominent, each filling a large portion around their respective cores with a smooth haze originating from the combined light of hundreds of billions of individual stars. Halos can also be seen around many of the other galaxies. Several of these show evidence of shell structures (http://www.rolfolsenastrophotography.com/Astrophotography/Centaurus-A-Extreme-Deep-Field) which are an indicator of past or ongoing mergers between galaxies.

Intracluster Light
Intracluster Light (IcL) (http://ned.ipac.caltech.edu/level5/March07/Mihos/Mihos5.html) is the feeble glow of stars not gravitationally bound to one particular galaxy but still bound to the cluster as a whole. IcL is incredibly faint and difficult to detect because its brightness is typically well below 1% of the sky background. Over time gravitational interaction between the cluster members tend to strip individual stars from the outer regions of their host galaxies. Flung far out into the combined gravitational field of the cluster the glow from these stars merge to form a weak diffuse light. The structure of this light can provide important clues about the cluster's dynamics and its past history.
The IcL is difficult to distinguish from the IFN (see below) which also covers the entire field of view in this image. But the upper NGC 3258 group of galaxies clearly has a diffuse trailing glow that extends right and downwards above the more massive NGC3268 group. Both groups also appear somewhat connected by a bridge of material which possibly also reaches out further down to include the delicate Sa spiral NGC3269.
Delicate red filaments of the Antlia Supernova Remnant (see below) are superimposed on the space between the two subgroups, complicating the distinction between sources of diffuse light in this area. Further from the galaxies the fading IcL is drowned by the IFN which covers the entire field.
A contour plot (http://www.rolfolsenastrophotography.com/Astrophotography/Antlia-Galaxy-Cluster/i-DTnHd7C/A) of a version of the image with reduced stars give a clearer view of the distribution of IcL and IFN light across the field.
For more details on Intracluster Light see Interactions and Mergers of Cluster Galaxies (http://ned.ipac.caltech.edu/level5/March07/Mihos/paper.pdf) by J. Christopher Mihos.

Integrated Flux Nebula
Visible throughout this image is a thin veil of wispy filaments; ghostly structures that are now known as galactic cirrus, or Integrated Flux Nebula (IFN). Only a few decades ago such structures were often removed in image processing, as they were thought to be instrument artifacts or similar image defects. However, these ultra faint patches of nebulousity are real and consist of thin traces of gas and dust which is not directly illuminated by stars but merely reflect the extremely faint combined glow of the Milky Way.

Antlia Supernova Remnant
A faint stretch of reddish nebulousity seems to extend upwards across the top (Southern) edge of the field. This is likely associated with the recently discovered Antlia Supernova Remnant ( http://www.researchgate.net/publication/231067942_Discovery_of_an_Old_Nearb y_and_Overlooked_Supernova_Remnant_ Centered_on_the_Southern_Constellat ion_Antlia_Pneumatica) which covers 24° of the sky, centered on the Antlia constellation.
This ancient structure is faintly visible in deep Ha exposures and also emits significantly in X-rays.

A Micro Dust Cloud Superimposed on NGC 3269
NGC3269 is one of the most interesting galaxies in the image. This appears to be an Sa spiral surrounded by several tidal loops and clumps. A particularly curious feature is a tiny 4 arcsecond wide brown dust cloud superimposed on the bright blue spiral arms. There are even two smaller (0.5 arcsecond) cloudlets of which one is visible in this image.
Here is a comparison of the micro dust cloud with an image from the 6.5m Magellan Telescope (http://www.rolfolsenastrophotography.com/Astrophotography/Antlia-Galaxy-Cluster/i-fgcM3NZ/A)
These are suspected to be unique small foreground dust clouds of a previously unknown type. For more details on this peculiar feature see "A Tiny Galactic Dust Cloud Projected onto NGC 3269?" (http://iopscience.iop.org/1538-3881/130/3/1141), B. Dirsch et al. 2005 The Astronomical Journal 130 1141

Notes on Data Acquisition and Calibration
Data was gathered over 55 different nights during the course of 6 months, from January to June 2015, with an accumulated total of 152 hours of data. The equipment used was a homebuilt 12.5" f/4 Serrurier Truss Newtonian on a Losmandy G-11 mount, QSI683wsg-8 CCD camera and Astrodon filters.
To enhance the visibility of the supernova remnant 8 hours of binned H-Alpha data was acquired. The binning served to increase sensitivity and thus pick up more of the signal, though at the cost of some resolution. However, since the supernova remnant is primarily a diffuse large scale component, the loss of resolution was acceptable in order to enhance this aspect of the image.
Data gathering began on 1st January 2015 when the Antlia Cluster reached an acceptable altitude in the East around 1am and then continued each clear night through the changing seasons until the cluster was no longer visible in the West due to trees and hills.
Typically 4-5 hours were gathered on each clear night (http://www.rolfolsenastrophotography.com/Astrophotography/Antlia-Galaxy-Cluster/i-Srn3rTh/A), but this naturally decreased after May 2015 when twilight began to limit the available observation time of the progressively earlier rising cluster.

Each of the 1630 raw subframes were calibrated using darks, flats and bias frames obtained at or near the typical operating temperature of the CCD camera in summer (-25C). Because the light frames were acquired over a six month period, while the seasons progressed from summer to winter, the actual CCD operating temperature ranged from initially -25C down to -32C towards the end of the project (as low as possible in order to minimise noise). All light frames were calibrated using PixInsight's automatic dark/bias scaling to account for these temperature differences.
To ensure optimal calibration and flat fielding, and to minimise noise levels in the final stacked image, this calibration was done against an extensive set of calibration frames consisting of approximately 400 dark frames, 500 bias frames and 300 flat field frames in each channel; L, R, G, B and H-Alpha.

Image details:
Resolution: 0.859 arcsec/pix
Rotation: 175.381 deg
Field of view: 47' 36.1" x 35' 50.2"
Image center: RA: 10 30 10.285, Dec: -35 25 09.18Date: 55 nights, January to July 2015
Exposure: LRGBHa: 103:20:11:10:8 hours, total 152 hours @ -25 to -32C
Telescope: Homebuilt 12.5" f/4 Serrurier Truss Newtonian
Camera: QSI 683wsg with Lodestar guider
Filters: Astrodon LRGB E-Series Gen 2
Taken from my observatory in Auckland, New Zealand


I hope you'll enjoy this majestic cluster, and comments and critique is welcome as always.
I highly recommend taking a swim around the full resolution image and the other views linked above, rather than the small compressed versions attached here.

Regards,
Rolf

[codemonkey]

Holy ****...

[rustigsmed]

Fantastic write up and sublime work Rolf, grattis.
Will need to revisit this on my large monitor!

Ps also surprised you managed to nab 55 nights in 6 months!

Regards

Russ

[Atmos]

Can I just quickly say... I am in love with that telescope :P
What you have done is spectacular Rolf, I mean truly amazing. Just about to start zipping through the full res now but WOW :eyepop:

[Nicola]

An amazing job for an outstanding image, well done indeed!

[rmuhlack]

Inspiring, visionary work yet again Rolf. Surely this is the bleeding edge frontier of amateur astrophotography, internationally.

[Somnium]

simply fantastic. amazing detail and it is extremely interesting seeing the difference in the Luminance integration time and its impact on the data. did you limit your imaging sessions to good seeing conditions or did you take cloud free nights when you got them ? this is the type of astrophotography that is simply inspiring. congratulations on your efforts, it was well worth the wait.

[strongmanmike]

Very cool Rolf.

This is one of those images that is not really full of spectacular looking colorful features like the Sagittarius Trio, Vela SNR or Orion regions and a casual passing look might even find it a bit boring...so it is not until you look carefully and realise what it is that you are actually seeing here that the enormity and achievement is realised. The write up is very useful to facilitate this too, very well done :)

I have considered imaging this cluster a few times in the past but considered it a bit lacking in interesting looking galaxies...but then I wasn't considering spending 6 months imaging it either :lol: so thank you for doing the hard yards (understatement) and producing a deep and intriguing vista :thumbsup:

Mike

[andyc]

Comments and critique? I'm not sure I'm fit to critique your shoelaces... extraordinary image! And thanks for sharing the results of your massive project, and the interesting bits of research around features in the image - those dust clouds in front of the galaxy are very unusual.

[cometcatcher]

So, this is the big project you have been working on. To say it's truly spectacular is an understatement!

[alpal]

Hi Rolf,
I admire your work.
This has got to be an APOD.
The universe looks so large & interesting with deep pictures.
I would like to see the same entire picture in LRGB
but with say only 1 night equivalent of time - say 3 to 5 hours
just to get a comparison.
(I see you posted a single galaxy with many different total exposure luminance frames.)
I really think that what you're doing is the future of amateur astronomy if we want to do something of great scientific value.

cheers
Allan

[Shiraz]

This is a wonderful effort Rolf. Thanks so much for posting your results and the very interesting and illuminating associated write-up :thumbsup::thumbsup::thumbsup:.

[Slawomir]

Awesome, unique, inspiring...think you Rolf for sharing the fruits of your hard work. I will need to read your write up again, slowly, and I will be enjoying coming back to your image to watch it, soak it in and to appreciate it.

[troypiggo]

Spending that amount of time gathering imaging data is one thing, and that's huge. But the amount of work you've put into the supplemental information and writeup - to a noob like me - that looks like a PhD submission! The combination of both is absolutely monumental. Hard to believe, but you've exceeded your previous attempts by a mile. I have no idea where you can go from here, but looking forward to it!

PS - I'm off to read more on intracluster light. I'm familiar with IFN etc, but not IcL. :)

PPS - I'm interested to know more about the data acquisition philosophy on such a huge amount of data on a night by night basis. You mention 4-5hrs data collected each night, but it's hard to tell from your graph whether you'd do all L in one night, all R in another night etc, or if you gather less subs of all LRGB in the same night?

[multiweb]

Sublime picture Rolf. That's dedication. Excellent write up. Learnt a lot. Will have to come back and read and look again. That's a lot to take on. :thumbsup::thumbsup::thumbsup:

[Paul Haese]

Huge body of work Rolf and I cannot help feeling that 60 hours of that time could have been put toward another project. Law of diminishing returns would be applicable here.

The medium image is superb looking with lots of things to view and inspect. It looks very well processed. Great colour saturation and very nice detail in all the major spirals and despite my above opinion massive amounts of signal acquired. Without doubt a reason why mega data collection is a good thing, despite some critics thinking signal acquisition is ok for some and not for others.

When I went and looked at the high res version one on your site whilst it was smooth it had the appearance of being smoothed in some way. Maybe this is not the case but that is how it looks on my monitor. Some of my longer galaxy projects give this appearance if I apply some smoothing to the background. The stars also look a little odd, but those are very minor things compared to the overall effect of the image.

I suspected this was the region you were imaging that night we had that discussion many months ago of what you were imaging next. I spent a bit of time looking around and thought in the end this must have been your target.

I don't agree that this is a boring area at all. The differing types of galaxies present and the super nova remnant make for a very interesting looking image and well worth imaging.

In my opinion a very nice looking with loads of detail and interest. Certainly close to one of your best and worthy APOD should you obtain that. You have now inspired me to add this to my imaging list. Well done Rolf. :thumbsup:

[gregbradley]

Hats off to you Rolf, tremendous dedication and hard work to make a truly unique image.

I also am floored about your 500 darks and 300 flats - oh my god. I would love to see an example of a light calibrated with a regular say 6 set of flats and one with the 300, same with the 500 darks. Does it make much difference?

Those little galaxies are amazing and that dark spot on the inner side of the ring of that galaxy is very odd. It looks a bit like a dark hole. I wonder if it has a small dark hole there.

Greg.

[clive milne]

There is a lot to like about what you have done there Rolf (much of it already stated by others)

However, in the spirit of constructive criticism and in an attempt to apply the scientific method even at the philosophical level, there is not much to be learned through validation. So, I'll keep my comments to what I believe to be the area's which might be improved.

It is my opinion (and take that as you wish) that the limit of your rig is a product of the light (from the foreground stars) being scattered across the fov from the various optical surfaces in the OTA, including internal reflections. There are a number of ways to reduce this issue.
* Image areas of the sky which are far away from the galactic plane.
* Switch optical trains to minimise scattered light. (I suspect the good old RC design without a field flattener might enable you to go deeper still)

best
c

[JD2439975]

:eyepop::prey2::prey2: :2thumbs::prey2::prey2:
(Humbly kneeling before Zod).

[scagman]

Awesome image.

[el_draco]

That's a BIG FAT DITTO from me.... :eyepop:

[Octane]

Does it get any better than this?

The image, write-up, tid bits, presentation, etc., all world class.

You the man, Rolf.

H

[plantnerd]

WOW such an exceptional image very inspiring for me personally just setting up my observatory with 10" Newt to show what can be achieved and to strive for perfection.
Gets my vote for APOD.

[DavidU]

:prey2:

[Regulus]

Speechless Rolf.

Trev

[topheart]

Wonderful stuff.....!!

Thanks very much!

Tim

[SamD]

Hi Rolf, as many have said, great work !

Yes, it can be difficult to pick out any Intracluster light from the Integrated Flux Nebula. I've aligned a (linearly stretched) image from the WISE survey (12um W3 band) which may help.

In the survey image you can see many faint bands and patches, including a slightly brighter patch to the right of NGC 3258, which may confuse the identification of a intracluster bridge to the NGC 3268 group.

Based on the published radial velocities in the Principal Galaxies Catalogue and measuring the angular distances between NGC 3258 and 3268, these two galaxies are probably 1-2 million light years apart, so there could well be a stellar stream between them. There's quite a large difference (about 1000km/s) between the radial velocities of NGC 3258/3268 and 3269 which would normally mean that NGC 3269 is about 50Mly further away. However, it's more likely though that the large difference in radial velocity is just relative motion within the cluster, so there could also be a faint intracluster bridge between these galaxies too.

[graham.hobart]

Humbling Rolf, and an exceptional presentation.
Lots to see and learn
Thanks for sharing this wonderful project
Graz

[IanP]

Rolf, hats off to you :bowdown:
Definitely an APOD winner !!! :clap:

[AstroJason]

That is just incredible, simply stunning Rolf!!

[Rex]

Awesome project Rolf! Great write up and wonderfully deep image. Thanks for sharing mate, Top Notch all the way.

[jase]

Impressive to say the least Rolf. Enjoyed the write up and comparative images. I have few questions;


What was your methodology for combining such a large stack of sub frames? Did you group them into smaller masters, then combine the masters?
What was your FWHM tolerance for including a sub into the combine? You show a FWHM of 1.7" in one
If you've used 152hrs, what percentage did you trash due to not meeting the tolerance?
Do let us all in on your secret on how to capture quality LRGB data 2 days before full moon on the 4th April with an 12.5" F/4 scope!
Did you consider binning the RGB data given its not delivering any further resolution compared the Lum? Would have saved you some exposure time.

Looking forward to seeing your next deep sky extreme imaging adventure. :thumbsup:

[PRejto]

Bravissimo!

Your dedication has resulted in a spectacular image. Thanks very much for posting the luminance stacking results. Most interesting! Like Jase I am very curious about your methodology for dealing with such a large data set.

Thanks,

Peter

[lazjen]

Impressive image and a great write up. Congrats.

This was done in Auckland? How much light pollution do you have?

[SkyViking]

LOL, cheers Lee :)


Thanks very much Russ, yes the weather was pretty good here early in the year. As you can see from the bar chart I had a very good run in first half of Jan and another in Feb. Then as winter arrived there were fewer clear nights.


Thanks Colin, I think the telescope performs very well too. The Royce mirror is a joy.


Glad you liked it Nicola! :)


Thanks a lot Richard, I like to do these projects and try to reveal something new every now and then.


Thank you Aidan, I'm glad you liked the integration collage too. I included that to illustrate that it really does make a difference, also after 100+ hours.


Thanks very much Mike, I'm glad that I could relieve you of the chore of imaging this cluster :lol:. I did have the same thoughts initially; that this cluster might not be particularly interesting, but that perception quickly changed as I got more data and began to research the limited literature on it.
Since publishing the image I have also had confirmation from scientists that the Intracluster Light seen here is indeed real and not previously described, so it was nice to get a confirmation of my own analysis and interpretation :)


Thank you Andy, I'm glad you found it interesting as I do like to provide some background and analysis along with my images.


Thanks Kevin! :)


Thank you very much Allan. While I primarily strive to produce an interesting and captivating image from an aesthetic point of view the scientific value (if any) is certainly on my mind when it comes to images like this one.
For example the Intracluster Light seems to not have been descibed in literature before (see my reply to Mike above)


Thanks a lot Ray. Speaking of illumination, it would be interesting to calculate the total (nano)Watt hours picked up by the CCD for this image! :)


Thanks for your kind words Slawomir, enjoy the image there is a lot going on in the background as well, distant galaxy clusters etc.


Thank you Troy :) About data acquisition, I gave preference to luminance data whenever the Moon was not too bright and seeing was reasonable (Reasonable being somewhat arbitrary :)). You can see the different bars on the graph jumping accordingly. For colour I took significantly more R than G/B because the faintest galaxies tend to be red and moonlight doesn't brighten the sky much in R, except for a few days right at full Moon. G and B data still had to be limited to moonless nights though.


Thanks very much Marc, glad you liked the write up too! :)


Thanks for your kind feedback Paul. Re stars, yes in the corners there is a bit of distortion still which is a result of the Baader MPCC having very little tolerance as to collimation and tilt in order to produce perfect stars across the entire frame. This is something that has annoyed me more and more, and I've actually now replaced it with a Paracorr so watch this space :)
There is no smoothing as such applied, other than a bit of light noise reduction with a luminance mask. I did experiment with the sharpness of the stars though and found that their somewhat toned down appearance here is better suited for the presentation of the IcL and IFN structures which was something I really wanted to highlight with this image. Perhaps I'll revisit that in a future repro :)
As for the time spent, I don't think I could have brought out this level of deep detail with significantly less exposure time, as the integration progress collage shows. But of course diminishing returns do apply at some stage.

[SkyViking]

Thanks so much Greg. About the darks/flats, they do add noise to the final stacked image so it's important to keep the master dark/flat as clean as possible. I can imagine using only 6 darks/flats would add quite a lot of noise to the final result! I did an experiment to test this a while back and could clearly both measure and see the difference. Taking several hundred darks and flats may seem like a lot of effort, but it's only once every six months or 1 year (I last updated my calibration library in Dec 2014).
With PixInsight's SuperBias script you can even create a synthetic master bias frame which is completely noise free. I used the script to create mine from 500 bias frames, which may be overkill - but at least bias frames are quick to acquire.


Thanks for your feedback Clive. You're probably right that a RC with less optical surfaces would allow slightly deeper images for the same integration time. However, that would require a significant investment in more expensive optics and new camera etc to match. A more capable mount would also be necessary to handle the heavier OTA. I did consider the RC design when building my OTA, but decided it's hard to beat the efficiency, simplicity and cost effectiveness of a fast Newtonian with premium optics. That said, I'm sure there's another scope waiting for me sometime in the future so we'll see :)


LOL, cheers Justin! :)

Thanks a lot John!


Thanks Rom :)


Thank you H, I'm glad you liked it all, I do try to put an effort into both the image and the presentation. It's nice to be able to tell an interesting story and bring the subject matter to life - and we're fortunate that nearly everything about deep sky objects is fascinating! :)


Thanks a lot Luis, and good luck with your observatory! :)


Thanks Dave :)


Thank you Trev :)


Thanks Tim, you're welcome! :)


Thanks very much Sam for the comprehensive info. I hadn't noticed the discrepancy in radial velocity between NGC3258/3268 and NGC3269, that's interesting. I don't know if the IcL extends to 3269 as it's impossible to see with the IFN interfering. It could be either or. Regarding the distance, I imagine NGC3269 is a member of the cluster and must be at a similar distance as 3258/68, because otherwise it would be an unusually large spiral if it's 50M light years further away.


Thanks Graham, it feels like a Hubble deep field with all the distant galaxies there and that is very humbling indeed. It's a big Universe! :)


Thank you Ian, hard to know about APOD there are so many great images to choose from these days.


Thanks very much Jason! :)


Thank you for the kind comment Rex :)


Thanks very much Jase, I'll answer your questions below:



Thanks very much Peter, see reply to Jase above :)


Thank you Chris. Yes I'm in Auckland, in the outer suburbs away from most of the light. My skies are 20.3 SQM which I think translates to Bortle ~5.

[DJT]

What a marvelous image! The write up is great, thoroughly enjoyed reading it along with :thumbsup:your answers to the questions posed here in the thread

Thanks for sharing

[marco]

:bowdown: Herculean effort Rolf! The result is outstanding and I do agree, the write up and all the job done on comparison with other images add a lot to an already unique image, bravo!
Marco

[gvanhau]

That's a master piece of image. :eyepop:

I photographed this cluster on Jan 2014 in one night, and none of the Ha filaments showed up. Obvius is that it is only work for a fixed setup. :lol:

Congrats.
Geert

[RickS]

An epic effort, Rolf! Not much that I can say that hasn't been said already :)

[Stevec35]

I've commented on this elsewhere Rolf but I'll say again - incredibly impressive work. You have amazing dedication!

Steve

[PeterM]

Its 2 things to me - visually stunning and its off the well worn beaten track and we should be seeing more of this. You have pushed boundaries here, so very well done!

[SkyViking]

Thanks very much David, I'm glad it was interesting :)


Thanks a lot Marco, it was good fun to produce all the supplementary views too, glad you liked it! :)


Thanks Geert, yes the Ha filaments are very faint and I needed 8 hours of binned Ha to even register them. A wide field image at lower resolution might pick them up faster I suspect.


Thanks very much Rick! :)


Thank you Steve, I'm happy with how it turned out in the end so felt the dedication paid off :) Not sure if I want to top this effort though :P


Thanks very much Peter, it was my intention to show something different both in terms of depth and subject matter so I'm glad you enjoyed it. :)

[IceMike]

Thanks for sharing this picture and the details Rolf. A stunning result for your effort. Congratulations!

[Rod771]

I think some professional guys are going to be upset with you Rolf. When governments see what your doing from your backyard they are sure to pull funding. :lol:

Thankyou for posting such an informative write up and inspirational image. Congratulations on your result! :thumbsup::thumbsup::thumbsup:

[White Rabbit]

I think Codemonkey summed it up quite succinctly.

HOLY ****

[SkyViking]

Thank you Mike I'm very happy with the result, so good to hear you enjoyed it :)


Thanks a lot for your kind words Rod, hopefully no funding will be pulled! :eyepop::lol:


Thanks very much Sandy :lol: :thumbsup:

[andyc]

I do believe this has finally got its well-deserved APOD! Long-overdue for a truly special image :bowdown:

[SkyViking]

Thanks very much Andy. it was indeed a surprise when I got an email from the APOD editors the other day, as I had submitted this image over a year ago.:eyepop::lol:

[Peter Ward]

I found this field anything but boring....in fact inspiring would be my thoughts
when I first saw the image at NASA's APOD site....well deserved!

Only after that did I see your post on IIS :doh:

Simply masterful, as usual, Rolf :thumbsup::thumbsup::thumbsup:

[topheart]

Mind blowing image!
Congratulations!!!

Cheers,
Tim

[rustigsmed]

congrats again Rolf, well deserved APOD! - even if it did take a while - just like the exposure time i guess! :lol:

[Stevec35]

Once again a great effort Rolf. Is your new observatory up and running yet?

Cheers

Steve

[alpal]

Well deserved:

http://apod.nasa.gov/apod/ap161018.html

[g__day]

Extremely impressive on all fronts - in awe!

[multiweb]

Pretty epic. 150h? Wow! That's like 4 years worth of clear skies in NZ no? ;)