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marc4darkskies
09-07-2008, 11:13 PM
Here is my rendition of the Eagle Nebula (M16). Total exposure 7 hours LHaRGB (90, 150, 60, 60, 60 minutes) gathered over 3 nights. I had to fight the Sydney weather (as usual) and poor seeing, but thankfully during my Lum and Ha sessions the seeing was reasonably good so the detail in the final result is respectable. Tantalisingly, there was one raw (30 min) Ha frame that was amazingly crisp – much clearer than any other frame. Must have been a bit of 1-2 arcsec seeing – can’t wait for the day when I get a few nights like that!! Unfortunately, the seeing wasn’t so good while gathering the RGB so I had to fiddle around a fair bit to even up the star sizes between the LHa and the RGB (to avoid too many ugly halos).

Small: http://www.pbase.com/gailmarc/image/99807021/large (http://www.pbase.com/gailmarc/image/99807021/large)
Large: http://www.pbase.com/gailmarc/image/99807021/original (http://www.pbase.com/gailmarc/image/99807021/original)

I blended the Ha with both the Lum and red channels (around 50% & 30% respectively). My LHa data was very smooth with a high S/N and only needed very light noise reduction in the darker areas. I applied some wavelet to the LHa. I struggled with the colour balance for a while in PS to cater for the Ha but I think I've got it right – I’m still a novice with Ha after all. :D

Hope you like it!

Cheers, Marcus

renormalised
10-07-2008, 12:57 AM
Not really great seein', he says.....looks like I'm flying through the damn thing!!!!!:eyepop::D:P:D

Great shots Marcus:D

AlexN
10-07-2008, 02:41 AM
Ha data really gives that image a fantastic kick in the pants effect!

Lovely shot mate... Inspirational.

Garyh
10-07-2008, 07:02 AM
Wow! I can tell you had some nice seeing with the Ha and Luminance.
Look at that detail!
:thumbsup:

Dennis
10-07-2008, 07:31 AM
Hi Marcus

Wow – that is a stunning image! I love the processing, revealing such a wide tonal range. The overall scene looks very 3D – a gorgeous portrait of this iconic object. Top stuff - thanks!

Cheers

Dennis

multiweb
10-07-2008, 09:27 AM
That's a great picture! You can really see the details in the pilars but you still kept nice soft colours in the stars. Great stuff. Awesome. :thumbsup:

iceman
10-07-2008, 10:01 AM
Wow that's a beautiful image, Marcus. Lovely structure and detail. Has real depth.

RB
10-07-2008, 10:03 AM
Superb image Marcus.
Very nice detail, you've done a great job with the extra Ha data.

jase
10-07-2008, 09:15 PM
Huh? bad seeing? Sure, sure. I can see that... Who are you kidding Marcus? This is a fantastic image. I'd say your sampling is optimal. Great work on managing the contrast of the Ha data. Well done.

Ric
10-07-2008, 10:43 PM
Lovely Marcus, very sharp and detailed.

A fine image.

Bassnut
10-07-2008, 10:46 PM
Excellent Marcus, both razor sharp and smooth, much detail there, a pleasure to view.

marc4darkskies
10-07-2008, 10:54 PM
Thanks guys for all the kind words - very much appreciated! :thumbsup:



Thanks mate! Yes, well, it really was poor seeing for the RGB. It took some effort to distill out the unwanted artifacts of that too - mostly affecting those pesky stars! :)



Thanks alot Alex! Ha is not easy (for me anyway) - plenty of trial and error processing steps - but it sure is a hoot when it ends up well.:jump2:



Thanks Gary. Yes, I lucked out. It's hard to find more than one consecutive night of clear skies in Sydney lately let alone one with good seeing. Like my M83 image, I got the good seeing when it really counted.



Thanks Dennis, glad you liked it! It took me a few iterations to draw out all the colour and get it looking natural. My first pass yielded a salmon + fluro pink/purple look. I almost thought it looked good too! :shrug: If you stare at and fiddle with an image long enough it ends up looking good no matter how bad it is. You've gotta go away and come back with fresh eyes - I had to do that multiple times over 5 nights of processing :screwy: :nerd:



Thanks Marc. Those pesky stars gave me grief though - should've gotten rid of them! ;) :lol:. I like achieving a certain softness with stars rather than crisp spots. Combined with smooth tonal transition this yields the "natural" look I like.



Cheers Mike. Glad you liked it!



Thanks for that Andrew. Ha is definitely your friend when you want detail but it sure makes colour balancing tricky.



Hey Jase, appreciate that! No really, it was bad seeing for the RGB ... honest! :) I still have the dark circles under my eyes from the "mitigation processing" I needed to do to prove it! :scared2: It was a labour of love though :D

Cheers, Marcus

marc4darkskies
10-07-2008, 11:06 PM
Hey thanks a lot Ric!



Thanks for that Fred! In spite of your aversion to stars :D;) I'm no stranger to your web site either! :thumbsup:.

Cheers, Marcus

dugnsuz
10-07-2008, 11:54 PM
You're in a different class Marcus - frighteningly good!!!

Matty P
11-07-2008, 11:37 AM
Impressive image Marcus, lovely detail.

Very well done.

skeltz
11-07-2008, 08:47 PM
Marcus,Marcus ,Marcus looks like you have done a pretty good job blending the HA data well done.
And a very nice crisp image to boot,i think you have done a very good job indeed!
cheers

marc4darkskies
12-07-2008, 12:02 AM
Sorry Doug - didn't mean to scare you!!! :eek:Hey, BTW, the world needs more astronomers, not more bass players! :D



Cheers Matty!



Thanks Rob - need more practice to improve my glacial processing workflow though. I discovered the channel mixing tool in PS recently and that helped with the Ha balancing act.

Cheers, Marcus