Ngc 5128 repro added

[Shiraz]

Hi
got about 6 hours (L+RGB) of quality seeing on this - not enough to get a lot of halo, but sufficient for the dust region. It was very pleasing to see some of the bright stellar regions appearing in and around the dust.
Thanks for looking - grateful for any feedback.
Regards Ray

http://www.astrobin.com/full/188224/0/?real=&mod=

repro http://www.astrobin.com/full/188285/0/?real=&mod=
(softened stars)

[Paul Haese]

That's nice Ray. Smooth and great detail. Well done.

[topheart]

Well done, a good beginning! I guess you will process it bit more to reveal more when you have a bit more data....what is your plan??

Cheers,
Tim

[strongmanmike]

Ray...seriously dude, these last three images of yours are out of this world. To think you are using a el'cheap'o 10" Newt one wonders why one would bother purchasing a $30K long focal length RC, CDK, ODK, RDiK or any other bloody DK you like, with $20K camera and FW on a $20K robotic mount :eyepop: :lol: (NB: I would still love any one of those DK's of course :D)

In all seriousness, I can see that decon was your friend on this one, I can see it but you have still handled it very well. It is clearly your expert use of decon (or similar) that is as much the reason for your spectacular resolution results as anything else, friggin good work fella :thumbsup:

Mike

[multiweb]

Top shot Ray! Love the colors on this one. :thumbsup:

[gregbradley]

Awesome Ray. I'm with Mike. I am consistently blown away by the quality of your images with modest gear. Sensational extraction of performance from your gear. Obviously that is as much a part of our pursuit as image processing is. Tuning our gear to sing.

Greg.

[IanP]

Of course +1 :D

[LewisM]

That is definitely right up there with the best of 5128 I have ever seen. What I really like mor ethan the GX itself is the background field - just beautifully handled.

Well done.

I hear the Deacon is your friend Mike ;) :P

[strongmanmike]

Only if he has a jet

[Peter Ward]

Weelll... as you asked...the core details look to have been locally sharpened, then heavily smoothed, ending up with a cartoon/posterised look to that region (to my eye at least) ... a minor quibble at best....

But...What a delightful Cent A! ....excellent depth and resolution that is pretty much seeing limited. This is a benchmark image that many will aspire to.

Nice one :thumbsup: :thumbsup:

[Shiraz]

Hi Paul. thanks very much.


Thanks Tim. Further data will depend on the weather, but I would be happy to leave as is for now. There are many other targets I want to image and at my age, not much time to do it:)


thanks very much Mike. I continue to be amazed at how good this little scope is - a bit rough around the edges maybe, but quite capable of seeing-limited imaging at my site. Fernando also just posted a good image from his similar 250f4.
This image had very little processing. A little deconvolution while linear (or maybe none at all, not sure if this or M104 was the one that didn't need decon) and a moderate amount of local wavelet sharpening around the core after stretching to tighten up small scale detail - I did not mask the stars for this, which makes it a little bit obvious, but the process brought out faint stars better, so it was left that way - might need to rethink that bit.


Hi Marc - thanks very much


thanks Greg. Yes, I have a lot of fun squeezing drops out of recalcitrant EO hardware - I did this sort of stuff professionally for over 40 years and it is great to be able to relax and have fun with it in retirement...


Thanks Ian


Thanks Lewis - appreciate the comments


thanks very much for the feedback Peter. I didn't use any smoothing at all on the core - only a little on the regions outside of the halo. The wavelet sharpening routine has some lightweight noise reduction built in, but I had that turned down, so am confident that the smoothness was inherent in the data. The sharpening contributed to the abrupt boundaries of the stars around the core - will modify that process in future, since I agree with you and Mike that it is noticeable.

regards Ray

[jase]

Marvellous image Ray. :thumbsup: Colours look bang on. May be a little too smooth for my tastes but can't please everyone. I'm enjoying these few images you've posted, I've visited them a few times today. Keep them coming mate.

[Shiraz]

Thanks very much Jase - you helped me earlier on colour issues, so I really appreciate the feedback. Peter also commented that the image looked over smoothed, but I only did a bit of sharpening and didn't use any smoothing at all around the core (apart from a little that is built into the sharpening routine) - the sky was nice and dark and this is pretty much how it was when stacked.

maybe I should add some noise :lol:

regards Ray

EDIT: had a look around and FWIW other images seem to show similar smoothness (not saying mine is in the same class, but the smoothness is similar - at least to my eyes). I suspect that the problem is with the sharp star edges. http://www.robgendlerastropics.com/CentaurusAAUS.jpg
http://www.capella-observatory.com/ImageHTMLs/Galaxies/NGC5128Center.htm

[Shiraz]

added a repro to hopefully address a star image issue. thanks Mike, Peter and Jase for feedback.

http://www.astrobin.com/full/188285/0/?real=&mod=

[strongmanmike]

Ah ok, wavelet sharpening seems to have a similar affect to decon on the appearence of the detail, ie it tends to reduce everything to point sources and gives the detail a uniform dotty appearance, this does tend to impart a high res "look" but to me this is not natural (or even real) and stands out very easily, even if one is careful and light handed. The good thing is that the dotty appearance hasn't extended outside the main dust lane area or into the background as is often the case in other more heavily deconed/waveletted images. Of course you have heard all this palava from me before I know :rolleyes: :) and as I said still a great image in all other respects.

Mike

[Rex]

Another Stunner Ray. Your images of late have been astounding. Great job mate!

[gregbradley]

The repro is perfection to my eyes. Well done. Mightily impressive.

Greg.

[nandopg]

That is an outstanding image. The outter halo is nice and smooth as should be and the usage of multi-scale wavelet for sharpening the core is spot on.

One of the best n5128 I´ve seen.

Fernando

[multiweb]

One for the cool wall Ray. You've surpassed marathon men in every aspect. :thumbsup:

[topheart]

Hi Ray,

Yes, now it looks finished indeed!! I thought the first version was a bit under-processed as there was so much detail obviously hiding in the softer version....this is wonderful, the sharper more pronounced core and the soft smooth outer areas...... wonderful tracking by your scope and good seeing obviously giving tight stars.

Your current version is much much better than my attempt about 5 years ago: http://apod.nasa.gov/apod/ap100313.html
Your stars are so much better - more colour, no artifacts and your processing more natural.
:thumbsup::thumbsup::thumbsup:


Tim

[Shiraz]

I agree with your philosophy. What I tried to do was keep it real by using the very hi res Capella image as a reference and ensuring that, if a detail appeared in my image it corresponded to something in the Capella image (see attached). The dots may actually be there in this case?


Very generous Rex - thanks


I really appreciate your comment Greg - thanks


thanks Fernando - all the best


Thanks Marc. Perhaps the marathon men still rule... Anyway, they are driving us all to up our games and have made a tremendous difference to our hobby, so good on 'em:).


thanks Tim - such generous comments from an APODer are much appreciated.

Attachment for Mike. Regards ray

[strongmanmike]

Ah yes.. unless of course they did the same thing :whistle:...

It's a fabulous image Ray, I think you know I think that :thumbsup: :love2: just musing over some processing ideas, t'is all :)

Looking clear as a bell here, have flexed off tomorow morning soooo, I'm going out tonight with some fresh inspiration caus'o you so thanks a miwion buddy :D

Mike

[LucasB]

Super image Ray. A real inspiration!

[gregbradley]

I am not sure what the concern is about decon. Its a valuable tool. I haven't seen any artifacts from decon except if used too hard you get harsh star rings.
So like anything in processing easy does it. But I am curious Mike as to what artifacts you see or suspect? Minimum filter can create a wormy pattern that does not in fact exist in the image but not decon or at least the decon I am using (CCDstack, positive constraint 5 iterations, auto select stars is quite mild).

Ideally I would prefer not to use it but it has its uses. One is when one colour sub has larger stars and you do decon on that colour channel only so you don't get bad coloured halos (tip from Marcus a few years back - very handy thanks Marcus). Also the multi scale decon technique from Ken Crawford is useful at times on a galaxy image.

Greg.

[strongmanmike]

It's the dotty looking detail (and often backgrounds), that's all, ie. when the details all start to look like various sized (mostly small) circular dots or thin worms it looks pretty obvious to me.

Not a biggy and as I said just light processing chatter :thumbsup:

Mike

[Harel_Boren]

Lovely Centaurus A through and through! What can I say that hadn't been said: great detail, wonderful halo, lovely starfield. A feast to the eye. Sheer delight!
Cheers,
Harel

[gregbradley]

I'll keep an eye for that as I hadn't really noticed it. So the background starts to look spotty. Yes I think know what you mean. I think that only happens with noisy data with low SNR to start with and if Decon is too heavy.

It'd be worth having a thread about decon. I am sure there are prerequisites for it to be successful. Like anything in processing it usually assumes enough data so that the shot noise is reduced. Its probably showing up the shot noise as if it were a real signal.

Greg

[Shiraz]

thanks Mike - hope it turned out well


thanks very much Lucas - appreciated


Thanks very much Harel - appreciate your generous comments.

regards Ray

[RickS]

That's a very classy 5128, Ray!

[tilbrook@rbe.ne]

Great work again Ray!:thumbsup:

I think the first image has the edge, just seems crisper overall.

How many subs did you reject if any?

I usually just eyeball each sub, probably not the best way.:question:

Cheers,

Justin.

[Shiraz]

thanks very much Rick and Justin.

Justin, I dropped about 1/3 of the subs due poor FWHM. Used Fits Image Grader to sort them - really handy bit of software.