The Heart of Sagittarius - M17

[RobF]

I've been lucky enough to get out with the rig a bit more this year, to the extent I trusted letting it go all out on a single object for a while. So in the immortal words of Kirk "Let's see what's out there....." ;)

This is a crop down on M17 from the full field, taken over a few nights.
LRGB 233:39:48:60 for just over 6hrs all up (Subs of 500secx1:180sx2:240sx2:300sx2)
QHY9 through the 8" Newt with IDAS LPS from the 'burbs.

I was surprised and happy to finally be able to get a bit of blue colour in my stars and brighter parts of the neb which was unexpected for "city data". Very happy all up, but keen to hear what others think re processing etc.

Larger versions available fullscreen in my album here (https://picasaweb.google.com/UserRobF/RecentWork#5623647362374796306)

[Ross G]

Hi Rob,

Smooth, sharp and great colours.

An excellent photo.


Ross.

[multiweb]

A truly splendid shot. Very well processed and captured! Best I've seen for a while of this object. :thumbsup::thumbsup::thumbsup:

[Deeno]

Lovely!!

[Dennis]

Hi Rob

Wow, I haven’t spent much time in the Deep Space section of the Forum recently and it has certainly been my loss when I see the quality of your images. These are beautiful photos and I love the processing that has revealed the curtains of nebulosity cascading down the frame. Lovely job!:thumbsup:

Cheers

Dennis

[telecasterguru]

A very pleasing image.

[jenchris]

Crisp and delighful - like a lettuce leaf!
Sorry no it's remarkable - beautiful the stars look so homogenous and real.
Proper 3Dish

[Omaroo]

Great job Rob. It's gratifying to see the QHY9 doing this from, as you say, the burbs.:thumbsup: I'll have to get mine out and actually use it one day.

[marc4darkskies]

A lovely rendition of an old favorite Rob. Nice and smooth with great detail and colour. Well done!

Cheers, Marcus

[strongmanmike]

Yeh that's a great Swan Rob, beautiful colours and some great detail, the radiating lines in the nebula behind the neck are a good indicator of the detail displayed, can't ask for much more on this one :thumbsup:

Mike

[Paul Haese]

I like the wider field of view Rob. It has a lovely balance to the image. Colour is good and very smooth. Well done.

[Stevec35]

Just about perfect in my opinion.

Cheers

Steve

[Hagar]

Thats lovely Rob. Nice and sharp tiny stars and great colours. I like it.

[jjjnettie]

You've nailed this one! It's a beauty.

[Screwdriverone]

Very nice Rob, colours and contrast, details are excellent......however....

It seems everyone is saying this is pretty much perfect, is it just me or are all the stars elongated in the South West quadrant (8 o'clock) position????

You can see it in the larger orange and blue stars....particularly eggy shaped. It doesnt seem to be coma as it looks constant across the whole field...

Not trying to be critical, but its the first thing I noticed and something seems amiss here.

Hope my eyes arent failing on me?

Can anyone else see this? :shrug:

Cheers

Chris

[strongmanmike]

Maybe you need one of these Chris? :lol:...the stars look near perfect to me, some slight flaring in the area you describe but nothing I would be concerned about.

[RobF]

Many thanks Ross :)



Thanks Marc - it was a really pleasant surprise when I started stretching this one just how the blues began to come up in the centre of the neb. I love those moments in this hobby - guess they're our "hole in ones" (or maybe just birdies? :question: ). Guess I'm understanding a bit more what drives people to do the 10 and 20 hr marathons now.



Thanks for looking Deeno



I'm glad you stopped by Dennis. Your photos have given me lots of pleasure over the years so that means a lot to me. :)



Thanks Frank!



Thanks Jennifer - I seemed to be able to crop in on this one a lot more than usual, probably because the amount of data has softened any nasties in the stars a lot more than usual. Glad you liked it.



Yep - hard to beat for bang for buck Chris. Really does open up new possibilities for those on a budget.



Thanks lots Marcus - I had your sumptuous colour schemes in mind a bit when I pushed this one must confess - love the wonderful hues of blues and oranges you make look so easy. Peter W's wonderful M17 repro recently inspiration too I guess.



Thanks Mike. I've put this one to the back burner to do for a long time because I thought it didn't have a lot to offer, but realise that wasn't at all correct. I was really excited at how much this one allowed zooming/cropping and a bit of upscaling - my images usually fall apart pretty quick as you close in. No danger of having as much real estate to swim in as the FLI's "SAO sensor" though!

Just wondering now - if a repro is a "Sidonio", then is cooking up a new abstract name for an object and FOV a "Mike"..... :question: :ashamed:



You can actually see the original FOV in an earlier image in my Picasa album Paul. I stumbled across the FOV shown while rotating and zooming to try and visualise the centre neb detail. Liked this aspect as it also accentuated the "heart" - I'm glad I was able to keep the brighter star in there in the end too.



No, never perfect Steve, but thanks anyway. Actually you always learn more trying to push better data, and I'm sure I could easily spend twice as long getting smooth star colours and playing a bit more selective sharpening of the neb. Then again, often you end up realising subtle and soft is best. As long as its fun :thumbsup:



I was really happy with this one Doug - think its one of my best to date - thanks for that :)



Thank you mi-lady :D



You're right Chris - they're not perfect, and in fact to my surprise collecting a lot of data actually smoothed the stars a little. Probably because the images have collectively been registered back on to the frame with the tightest and roundest stars. In fact I still routinely run with almost 2 inches of focuser tube protruding into the lightpath, so the mid-brightness stars frequently show a "bite out the apple" effect which is a little bit masked by one of the diffraction spikes. There's also a little bit of diagonal smearing where tracking has wandered in RA and DEC from time to time, but again stacking so much data averages out many of these evils. We're not talking Feathertouch focuser here either, so I suspect there's a smidge of movement with the focuser and camera mount fittings. I debated using some of Pixinsight's morphological transform functions get more spherical stars, but hadn't resorted to any noise removal and thought I'd try and keep it more "honest" in the end. I might have disguised these star issues a bit more by posting the wider field, but I really like this aspect, so posted the crops. :)

I may well go back to the PI guys and ask for their thoughts on workflow for this one. A had a few gos and only once was able to pull out anything like the stars colours here, so there's still far too much serendipity in the processing for my liking.



:lol: I think that's what the neighbours think I might be up to some nights Mike when they look down from their deck and see this guy with a "miner's light" stuck on his head poking around in the back yard..... ;)