Environs of NGC6188

[jase]

“Shazzaamm!” <smoke screen dissipates, figure emerges>:lol:

Hi All,
NGC6188 and its surrounding area have been on my wide field target “hit-list” for a while. After seeing Humayun’s (Octane) recent post (http://www.iceinspace.com.au/forum/showthread.php?t=21558), I thought I’d better get my act together and acquire some data on this fascinating region in the constellation Ara.

I am pleased to present, for your viewing gratification, NGC6188 Wide Field (http://www.cosmicphotos.com/gallery/nebulas/index.php?path=./&page=0&img=NGC6188%20Wide%20Field.jpg&idx=6).

There are a few interesting objects in the FOV which puts things into perspective (great pairings);

NGC6188 (main feature) – a complex emission and reflection nebula illuminated by the open cluster NGC6193 (aka Ara OB1).
NGC6164-5 (bottom – off center right) is a bipolar nebula surrounding the massive star catalogued HD 148937. Hey, Fred… how ‘bout targeting this one with your narrow field, narrow band filter set some time? I think it would come out a treat with narrow emission lines and long focal length. Not narrow enough for you eh?
Open star clusters: NGC6167 (lower left), NGC6200 (right of NGC6188) and NGC6204 (very top right of frame).A few on words on the image;
Total exposure time 2.5 hours (L:60min(4x15min subs),R:30min:G:30min:B30:min(5min subs). Image is an LLRGB composite. Large, flat, un-vignetted, wide field of view (155.8 x 233.7 arcmin to be precise). After blinking subs a few times analysing the data captured, what I originally thought was noise is actually stars. It’s very tempting to go Ha in this region as nebulosity is plentiful and star fields are rich.

Quick processing overview;
Typical routine - Dark/Flat/Bias reduced in MaximDL then registered in Registar, combined (median) in MaximDL. Two interactions of LR-deconvolution on the luminance in CCDSharp. L and RGB combined in PS. Duplicated RGB layer for later use. Used shadow/highlights to non-linear stretch the RGB data instead of curves. Curves were used for luminance however. L set to luminosity and set at 50%. Duplicated RGB layer levels increased to only see stars, no nebulosity, and then set to lighten blend mode to bring stars back to correct weightings. Flattened. Cleaned image – light use of healing tool and smudge. Added luminance layer again, but at 100%. Balanced tonal range and boosted saturation to taste. Duplicated layer and created high pass filter layer mask on copy. Selectively highlighted areas of interest to improve contrast. Flattened. Used colour range tool to feather selection of highlights and inverted selection so only dim areas were selected – used noise removal filter (this was a rather crude way of doing it, but it works ok – an inverted layer mask appears to work best). Lightly seasoned (colour balance tweaks).The presented view has a reduced image scale of 50% to make it web friendly. The full frame 8-bit version is 30Mb in size (original 16-bit/60Mb). Plenty of data to manipulate.

Thanks for looking and hope you enjoy! All comments welcome.:)

[Dennis]

Hi Jason

That is an exquisite image – just fabulous to bathe my eyes in, whilst drinking my morning cuppa in a sunny, but chilly 6 deg C Brisbane morning.

The 3D effect has me peeking over the rim of nebulosity half way down the frame, trying to peer into an imaginary cauldron illuminated by the bright cluster.

A fantastic effort in acquisition and processing – well done.

Cheers

Dennis

[Phil]

stunning shot Jase well done mate keep them coming. That setup you are useing is a killer. Love the weild field shot.
Phil

[Ric]

Very impressive Jase, you have achieved some real depth to that image.

Very nice indeed

[strongmanmike]

Excellent capture there Jase.

Nice processing.

Mike

[RB]

Jase all I can say is, that is stunning !!!
Always enjoy your work.

Thank you for sharing.
:thumbsup:

[[1ponders]]

Rippa Jase. What a smashing image. I bet you are happy with that one. Thanks for posting your processing as well. :thumbsup:

[Bassnut]

WOW Jase, pin sharp, perfect guiding, another classic. (and SO many stars).

[ballaratdragons]

Just as I said about Humayuns, "You've got a bit of everything in there!!!!"

Jase, that is certainly an outstanding image. Well worth the effort you must have put into it.

I also spot 2 isolated Blood-Red stars :)

[Dr Nick]

That is incredible!!!!!!!!!!

I wish I could get images that sharp!!!!!!!!! ;)

Keep it up!

[jase]

Thanks for the descriptive and somewhat poetic response Dennis.:) It’s a remarkable area of the sky for wide field work.



Thanks Phil. I’m still learning the ropes mate. :D I looked at some of your old posts on narrow band wide field work. It’s awfully tempting to go down that path next.



Cheers Ric. :) The image does have some depth to it with 3d molecular cloud.



Thanks Mike. :D



Cheers Andrew. :) It’s a pleasure to share my experiences with all.



Thanks Paul. Yeah, it turned out reasonably well. I’m not trying to talk it down – it is a good image, but having spent a few days working the image over I think I can improve on it. Actually two of the subs I combined shouldn’t have been included due to data errors. The median algorithm partly sorted it out. If you know what to look for, the errors are still there (of course I’m not going to state what they are):whistle:



Cheers Fred. I know this wide field wooze stuff isn’t your game.:P



Thanks Ken. I spent approx 7 hours processing (not consecutively). Those blood red stars are actually defunct hot pixels (kidding) ;)



Thank you Dr. Nick :)

[tornado33]

Excekent colour rendition there, the subtle blues stand out as well as all the red Hydrogen
Scott