M17 - Swan nebula

[Rod771]

Been a while since I've had some new data to process. June and July new moons where either clouded out or work commitments dictated early bed times. :zzz: This month proved to be different. :2thumbs:

This is my first shot of M17 at my long FL configuration. Ended up with 86 x 4 minute subs imaged over three nights.

Imaged with the C11 Edge HD with .7x focal reducer (1960mm FL) F7.
Mount - CGEM DX
Canon 60Da @ ISO 800

Integration, 5 hours 44 minutes in total.

Calibrated with darks and flats, processed in Pixinsight.

Large click here (http://astrob.in/full/203919/B/)

Full click here (http://astrob.in/full/203919/B/?real=&mod=None)

Thanks for looking

Cheers

Rod

[tilbrook@rbe.ne]

Nice Rod!:thumbsup:

Some great detail in the centre of the Swan.

Cheers,

Justin.

[Rex]

Stunning Rod. I like it a lot. Great colours and really nice detail in the Neb.

[Somnium]

Beautifully done !

[DJScotty]

Stunning image. Superb detail and colors.
Love it :thumbsup:

[Paul Haese]

That is a pretty slick Omega there Rod. Good detail and star colour looks good too. Maybe the nebulosity looks a little brown, but there is lots to like. Nice smooth back ground too. Well done :thumbsup:

[strongmanmike]

Really good Rod! What a vista, I like seeing the Swan in this orientation, anything else looks wrong or upside down to me :shrug: :screwy: :lol:

MINOR POINT...The wavelet/sharpening ie bright thin lines, is still juuust visible though :scared3:..maybe a slight re-blend to satisfy my obsessive compulsive wavelet/decon phobia....please? :face: ...or, just ignore me :question: :lol:

Mike

[multiweb]

Great shot Rod. Nice image scale. Tight stars and beaute colors. One for the cool wall. :thumbsup:

[RobC]

Top marks Rod. You are creating excellent imagery.

Rob

[Rod771]

Thanks Justin! I was pretty please with it.



Cheers Rex! Glad you like it mate.



Thanks Aidan! :thumbsup:



Thanks Scotty, It was good to have some new data to play with after a couple of months.



Thanks very much Paul! :) I normally just go with what ever PI's colour cal comes up with but with this one, I pushed the red channel in curves a bit to showcase a bit data/signal. Perhaps I pushed it a touch to far creating the brown?



Thanks Mike! :) Yeah I get dizzy when M17 is in any other position. :screwy:

Ah yes :) You know what Mike, every time I include my decon routine in the work flow, I have a little Mike Sidonio sitting on my shoulder whispering "That's too many iterations, back it off a bit or he'll notice" :lol: I did also do some wavelet sharpening at the end too, maybe that was too much?



Thanks Marc! Yeah the stars are getting better I think? I have noticed I have a bit of backlash in RA that I could probably tighten up mechanically, which may help guiding and results in future. The full image is a 50% resample of the full res and the biggest resolution I've posted, so I'm slowly gaining confidence in data acquisition and processing.



Cheers Rob! Really enjoying it at the moment. Thanks for the support. :thumbsup:

[strongmanmike]

:lol: Sorry, it is more my problem than yours I think Rod :nerd:, there are plenty out there that wouldn't even notice :thumbsup:. I just think detail needs to be real and not manufactured, wavelettes and decon do manufacture pseudo detail if not very careful. If you can see thin bright wiggly lines or tiny uniform dot like detail...it's a dead give away. It is only subtly noticeable in this image anyway.

Now...where's my straight jacket :scared2:

Mike

[RobC]

Mike - Curiosity has got the better of me. Please draws some arrows on Rod's image to show where the wiggly lines or tiny uniform dot are created by the deconvolution processing.

Thanks

Rob

[IanP]

Uhh :shrug: … I can’t see the wiggly lines or tiny uniform dots; my spectacles must be out of date …
But without them what I can see is a really fine M17 :eyepop:

[strongmanmike]

No need for me to draw arrows all over Rod's image, the effect I notice is only subtle and I'm not going to subject his Swan to disfigurement by pointing out some minor artefacts in her feathers, if you can't see'em then that's good :thumbsup:. Besides, I think Rod knows what I am saying, the image is really quite good and my observations were of something fairly trivial and my comments were just friendly and light-hearted :)

Mike

[Paul Haese]

I can't see any either. Must be like jets. ;)

[strongmanmike]

Or noise ;) ;)

[pluto]

Wow, that is an excellent image!! Great work :)

[Geoff45]

Nice work Rod. Good wide field and lots of sharp detail. I would push the saturation a bit more, but I guess that comes down to personal preference.
Geoff

[Rod771]

Thanks Ian :)



Cheers Hugh!



Cheers Geoff!

Thanks for the feedback. I must admit I'm conservative (or indecisive) when adjusting colour saturation.

[Rod771]

And that's the way they were taken, Mike! :) I always appreciate any feedback and definitely enjoy your humor :D. I think we're on the same page there. :thumbsup:

[strongmanmike]

Cool :)...but of course I knew that, I was just making sure others knew it too :thumbsup:

Mike

[Rod771]

We cant discount Mike's experienced eye, he has correctly identified the techniques I applied to the data. Lets look at what he is referring to for the benefit of the thread.

Below are three 100% crop sections of the synthetic Luminance data extracted from the RGB channels. Decon was only applied the synthetic luminance.

Image 1: Before deconvolution
Image 2: After deconvolution (applied to linear data)
Image 3: After decon and wavelet sharpening (applied to non linear data with star mask active)

I normally include decon in my workflow but try and keep the iterations quite low so not to introduce unwanted artifacts. Also remember I was cheeky and re sampled the 100% full res to 50% and posted that image to Astrobin. This will make it harder but not impossible, to spot any deficiencies.

The backlash slop in RA is evident in the images, if I can adjust this out a little mechanically, then the data will benefit and the detail will tighter at integration.

For me, its about (hopefully) producing pretty pictures. Do what ever you need to to get them and share them with your friends. :)

[strongmanmike]

Glad you did that Rod, better than drawing arrows on your image :lol: and thanks for revealing my (apparently) invisible jet, after many years of processing images, little flies under my radar now :nerd: ...wonder if I should start calling out the growing and rather obvious use of Russ Cromans Star Shrink tool :question: :lol:



And that is the way it should be and hey, looking at what you started with, mate, you used clever processing - a fine job indeed :thumbsup:


Mike

[RobC]

Rod,

Thanks for posting the images showing your enhancement methodology. I have been really impressed with the last few images you have posted and wondered how you were achieving the detail and clarity in your images . Now I know.

I am a newbie at this , but no where can I see any evidence of manufactured data with your enhanced image. These images highlight the power and intelligent application of the PI tools you are using.

Keep the images coming.

Cheers

Rob

[Paul Haese]

I still don't see a problem with anything you have produced here Rod. The sharpening is not over done as I see in quite a few images. Like you, my aim is for pretty pictures and this is a very nice image. The use of deconvolution has enhanced the image and not degraded it in my opinion. I personally don't use decon and use other sharpening routines but see its merits. It's use is not obvious at all in this image and I respectfully don't agree that it should be pointed out when it is not obvious. There are no worms or dots visible in the image. Hence my comment.

[Camelopardalis]

That's a beauty Rod :thumbsup: so much detail!

[strongmanmike]

Well, I actually said "manufacture pseudo detail" which is not quite the same and Rod just showed us exactly how he used PI to manufacture this pseudo detail :shrug:...and it always imparts the same tell-tale "look" to details that is easy to spot.. I could be wrong but I recon Rod would be very happy to remove the RA backlash and like us all, place his scope under arc sec seeing, so the detail would be raw and not need as much enhancement by complex but imperfect algorithms that approximate the real detail.

None of this makes it a bad image, it is just easy going processing small talk :thumbsup:

Mike

[RobC]

Mike,

I really don't know what you are on about trying to discredit PI's deconvolution procedures. There are many schools of image enhancement. You have yours , and there are many others. None has the insight to know how an object should appear so there are many interpretations. To imply one interpretation is false is nonsense. :thumbsup:

Cheers

Rob

[strongmanmike]

Huh? wha tha? I'm not :shrug: sorry if you have misinterpreted this Rob, that was not my intention, it is mostly just the amount/settings that get used, or how it is blended in with unfiltered data, same as for any filter in any piece of software.

I am not implying that an interpretation is "false" just that the detail can be manufactured from essentially corrupted data and this is inherent in the whole sharpening deal no matter what the software. It's just that some filters/processing techniques can be a bit obvious if not careful and usually we try to avoid this or it looks unnatural. The only way to really completely avoid unnatural looking sharpening routines is to have perfect optics under perfect seeing. If the filters used on an image can be identified then that is probably a sign that they may have been applied a little too hard, that's all. :)

Mike

[multiweb]

Oh C'mon mate! :shrug: You never sharpen your shots? Of course you do. We all do. Perfect optics on a perfect mount under perfect seeing? Never gonna happen. I thought Rod did a sterling job at enhancing his shot. TBH I can't even see any sharpening defects. And if he wanted to deconvolve the buggery out of it then go for it. Dealer's choice. Storm in a tea cup. ;)

[multiweb]

Try Startools Star Healing algo on your oblong stars. It will make them perfectly round without touching the rest of your image.

[strongmanmike]

Point and missed..? :question: storm in a tea cup is right, so why add more wind Marc? The OP 100% gets my comments but onlookers don't and get narky, funny game this :)

[multiweb]

Let me guess... cloudy in Canberra? :rolleyes:

[strongmanmike]

Raining actually :)

[Rod771]

No problems Rob.



Hey thanks Dunk! I'm happy with it.



That's called Morphological Transformation in PI land Marc. :) I did use it in the work flow but at a later stage when the luminance had been combined with RGB. So the cropped images above do not have it applied.

Thanks for the tip though. :thumbsup:

[multiweb]

Here you go. Just learnt another PI process. :thumbsup: The names are much harder to remember than the actual functionality. :lol: At least this one is human readable and not some weirdass acronym. ;)

[Camelopardalis]

I'm just waiting for the transmogrification button, then I won't have to worry about which functions to use in my processing :D

[multiweb]

:lol: I reckon they're all made up names lost in translation. Aren't the original buttons in Spanish anyway? Like Ole! Hasta La vista! and other interjections. :P

[Camelopardalis]

:lol: :lol: :lol:

[Rod771]

Riiiiiick!! They're laughing at Pixinsight! :D

[multiweb]

He's in Spain. He can't hear us.

[Placidus]

Only just looked at this one. Very fine. Lots to see.

[Rod771]

Thanks Mike and Trish! :)

[RickS]

Nice image, Rod!



They are welcome to do so, Rod. As the righteous acolytes of the one true way we can afford to be smugly dismissive knowing they will one day be fodder for the deconvolution worms while we ascend to MultilayerWaveletTransmogrification Heaven :lol:



I'm back! I didn't think about it but perhaps I should have looked up the PI dev team guys while I was there :question:

[Rod771]

Thanks Rick! :)




:lol: That's quite good.

[strongmanmike]

Sounds like a line from Star Trek...or maybe Blazing Saddles? :question: :P

[multiweb]

I guess your vision might have been impaired behind that gigantic beer mug. :cheers:

[RickS]

The 1 litre beer mug is certainly a wonderful thing in a hot climate :thumbsup: