M83 alternate processed image

[gregbradley]

I got some reasonable seeing so I started doing a fresh M83.

I got some nice data. I added to it over several nights.

I liked the detail and the colour that came from it. I have always liked that nice blue shade M83 images sometimes capture. I think the blue response on this SX694 is superb and I managed to get that blue that has been elusive in other versions I have done.

http://www.pbase.com/gregbradley/image/156443727/large

Greg.

[alpal]

Very nice Greg,
The bright stars might looks a little better if you select them in Photoshop -
expand & feather then adjust curves.

cheers
Allan

[gregbradley]

Thanks Allan.

I don't mind the stars and they are very natural with no processing applied to them. In fact I quite like the stars in this image. They are quite tight and pretty spot on at over 2 metres focal length. I took many hours of this object and only used the very best seeing subs to get the best stars. That PS technique can work on some images (perhaps better on widefield images) but it also can leave dark rings around the stars which is a step backwards. To my taste I prefer the more natual less processed look where I can get it and strive for better basics for tighter stars etc. Corrected Newts seem to have the tightest stars for the same image compared to other scopes. The CDK is quite good as well but at 2-3 metres seeing is everything. An AO unit is something that would be nice at times (well all the time with this scope!).

Greg.

[RickS]

Hi Greg,

The stars look a little hard to me too, at least with the image at "original" size. Also looks like a bit too much noise reduction up close? Could be my crappy laptop screen though... The data looks great but maybe a little more tweaking is needed?

Cheers,
Rick.

[johnnyt123]

I think its fabulous.

However i see what Allan and Rick are saying.
perhaps just tone down the brightest stars to add a little depth to them.

but i still love this image especially the colour of the galaxy and nebulae...

well done

John

[gregbradley]

Ah yes I see it now. Its the dreaded decon!:lol: I've softened the stars and muted them a tad using a different approach. Yes better now.



Cheers John. Adjusted, it does look better now. Decon can give stars a hard edge sometimes, the downside of it.
I was very happy with the colours, much better than I have captured before. I am wondering if the blue response of this Sony chip is superior as I have seen that lovely blue colour before but only from very large telescopes. Usually the colour is bit more cyan.

Greg.

[cometcatcher]

It is a wonderful image. Lots of Ha regions too.

A pity my 16" isn't driven. I'd like to have a go at it with a big scope.

[gregbradley]

Thanks very much. The Ha was quite clear and prolific in the Ha subs. This galaxy has very extensive Ha regions.

Greg.

[tilbrook@rbe.ne]

Fabulous Greg!:thumbsup::thumbsup:

Detailed and smooth.
Colour is very pleasing.

Cheers,

Justin.

[strongmanmike]

Some great things about this image Greg, as usual the image scale is great, the HII regions stand out nicely and those two distant companion galaxies always look good when revealed as clear spirals :thumbsup:. To my (err?..red biased :question: :lol:) eye though I also think the noise reduction/smoothing may be contributing to giving the details a bit of a broad brush painted look, this is less obvious at the smaller size though.

Mike

[gregbradley]

Thanks Justin. I was pleased with it.



Thanks Mike. Tbe only noise reduction was done on the very outer dim spiral, nothing on the main body of the galaxy. Its relatively short exposure despite taking several days of it (most was thrown out). More exposure as usual would improve things. I have some other data from earlier times I might try to add to it if the data is good enough.

Greg.

[strongmanmike]

Interesting...some other processing technique must be causing that look then?..do you know what I am refering to?

Either way plenty of good in the image too :thumbsup:

Mike

[marc4darkskies]

Overall this is a lovely image Greg. :thumbsup:

But I do see what Mike is talking about - the inner portions look a bit over smoothed. Not sure why it would look that way without noise reduction though :shrug: Did you apply sharpening, unsharp or other filtering to the central bits?

Cheers, Marcus

[Marios]

Just amazing detail.. Beautiful.

[telecasterguru]

I like the image as well. It seems very natural to me.

Frank

[gregbradley]

I had another look at it more carefully comparing it to an earlier version in the processing sequence and you are right something has smoothed out the galaxy unintentionally. The earlier versions before that step were sharper.

So I have taken on the various comments about softening the brightness and edges of the stars, making it sharp etc and put it all together and I think this final version seems to address them all. Overall I think this is the best M83 I have done so far even though it was less data.



Cheers Marcus. As mentioned above I looked again and you are both right there had been some smoothing that entered in unintentionally at some point. Corrected all the various points now.



Thanks very much Marios.

Greg.

[gregbradley]

Thanks Frank. I did try to keep the processing minimal but I ended up doing a bit more than I wanted but its subtle at least!

Greg.

[graham.hobart]

I really like it Greg, I like the Ha particularly and the core. It does look natural.
IS this the new trend in processing?, a more organic feel?
Even holistic!!!
Here comes the essential oils and the chanting !!

[strongmanmike]

OK at the Pbase "large" size it does look pretty cool, colours look good and the HII regions look amazing really..but at "original" size the processing does show up but ya know what?.. who cares..a great shot of an amazing galaxy :thumbsup:

Mike

[gregbradley]

All organic foods consumed whilst processing this image!



I see, yes. I removed one high pass filtering step and it holds up better at original size now. Essentially that is how it came down from the setup.

Greg.

[Rod771]

Looks awesome Greg! Love the colours. :thumbsup:

[gregbradley]

Thanks Rod.

Greg.

[allan gould]

After seeing all the suggestions in processing I think your final image has everything squared away to give a really clean image. I would be more than happy to approach such data.
Been busy for a month in China and just managing to troll through the 2500+ images from the EM5 before printing them in two volumes - so that's my excuse for not catching up on your latest image.
Looking really good, Greg.
Allan

[gregbradley]

Thanks Allan. The various suggestions are helpful as I sometimes miss these things when processing that othes pick up.

Greg.

[gregbradley]

I've been studying more on image processing and applied some of it to this image and got this alternate image of my recent M83. It holds up better under zooming in.

http://upload.pbase.com/gregbradley/image/156547980/large

http://upload.pbase.com/gregbradley/image/156547980/original

The original version is here:

http://www.pbase.com/gregbradley/image/156443727/large

http://www.pbase.com/gregbradley/image/156443727/original

Which do you prefer?

Greg.

[RickS]

Yes, I like the new version much better, Greg.

[cometcatcher]

Is there less data in the new one? Although it seems more natural, there is more noise and some of the fainter stars disappear.

[alpal]

It's beautiful Greg.
I like how you weren't afraid to leave a bit of red noise in the background.
That way everyone can see where the noise level is & makes the pic super honest.
Also - it's not over sharpened.

Well done

Allan

[gregbradley]

Exactly the same data just processed differently. I can check for the noise levels I thought I had reduced them enough but perhaps not. I see there is still some red noise in the background. I have reduced it without affecting the galaxy. Still a small amount must be background noise from the Ha layer early on. Minimal now.

Fainter stars are still there is just less contrast compared to the original in that regard so it appears to me they stand out less.



Cheers Rick.



Thanks Allan. Sharpening is a trick in these astro images. Its easily overdone.

Greg.

[allan gould]

Another excellent repro, Greg. I prefer the latest version as it appears just slightly less pushed in the processing than the last.
It's difficult to asses sometimes as good data can give many different versions and it really comes down to either personal tast or pixel peeping.
Allan

[gregbradley]

Thanks Allan for your feedback. I agree there seems to be different ways of presenting the data.

Greg.

[Shiraz]

well that was an interesting journey. The final image is a ripper - beautiful colour and remarkable detail.

[gregbradley]

:lol: Thanks Ray. Processing an image seems to be an evolving refinement of technique. Learning new ones that work better than old ones. So it was here.

Greg.

[DJT]

Hi Greg

That rework holds up really well. It's a great image. :thumbsup:

[gregbradley]

Thanks very much David.

Greg.

[multiweb]

I thought the original was average in details but the repro is superb. Love the Ha regions and faint brown dust extending into the outer spiral arms. Lovely colors too. Wow factor. To the cool wall. :thumbsup:

[gregbradley]

Thanks Marc. I haven't had a good run with M83 images in the past so I am happy with this result.

Greg.