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View Full Version here: : RCW 32 aka Gum 15 aka Southern Trifid


Geoff45
08-02-2019, 01:33 PM
This is not a very commonly imaged object and not the easiest to process.

Full res image here (https://www.astrobin.com/full/389723/0/)

It was taken last Sunday at Wiruna. The on-again off-again clouds were a pest but I managed to get about 5 hours of good data out of 7 hours of imaging.


Details:
Telescope: 12.5" Plane wave CDK
Mount: AP900
Camera: FLI 16803 Proline
Exposure: 60 min L, 50 min R and G, 60 min B and 70 min Ha.
FOV: 49' x 49'
Acquisition: MaximDL

Processing: PixInsight


For the luminance I made a superluminance by combining the L, R, G and B masters. The Ha was eased into the red channel near the end of processing using PixInsight's NRGBCombination script.



It's hard to get much info about this object, but here is a combination of bits of stuff I could find:
Gum 15, also known as RCW 32, is about 3,000 light-years away in the constellation of Vela. It is shaped by aggressive winds flowing from the stars within and around it. The bright star near the center of the nebula is HD 74804 which is responsible for ionising the gas. The central region shows dark patches of dust, while deeper pictures show some faint reflection structures crossing it that are only dimly visible in this picture. The various combinations of emission, reflection and dark nebulae make the nebula resemble a larger and fainter version of the better known Trifid Nebula.

Peter Ward
08-02-2019, 05:14 PM
Some minor chip defect quibbles, but a very classy image.
Nice :thumbsup:

gregbradley
08-02-2019, 05:45 PM
Nicely done Geoff. It looks great.

Greg.

Placidus
08-02-2019, 06:00 PM
Good to see something new and fresh. Subtly and gently processsed.

Guessing that this is a youngish area, without too much in the way of past supernova explosions.

How do you find the Proline 16803 ? We're literally within hours of ordering one as a replacement for our dead Aspen 16803.

Best,
MnTi

willik
08-02-2019, 06:35 PM
Very nice image Geoff looks great :thumbsup:
Martin

Geoff45
08-02-2019, 07:07 PM
Thanks Peter. I should go back and fix it up. I spent too much time looking at the nebula without paying enough attention to the outlying areas.


Thanks Greg


Thanks for the positive comments MnTi.
Regarding the Proline:Nice big field, -30 deg all year round, fast download, there is a tendency for column defects as Peter has mentioned, but they can be corrected if one doesn’t rush unthinkingly into the processing.


Thanks Martin.

Peter Ward
08-02-2019, 10:34 PM
So I can't interest you in a STX16803 with Adaptive Optics :D

strongmanmike
10-02-2019, 09:32 PM
Lovely result Geoff. Andy might tick you over the composition..? :whistle: but it looks quite lovely and rather Trifid like. Nice job after what sounds like a slightly testing evening of capture :thumbsup:

Mike

cometcatcher
11-02-2019, 01:40 PM
That's stunning. Love the Gums. Wish I could get some time on them but they are poor weather targets.

Geoff45
12-02-2019, 04:38 PM
Thanks Mike. The problem was mostly thinhigh cloud. Often while I’m imaging I do some casual stuff like identifying the far southern constellations. So I was looking for the S Pole in an apparentlycloudless sky, bright stars everywhere. The SP is between Acrux and Archenar. Whoa! No Archenar. That was the start. It got worse then better then bad again etc as the night wore on. Still, the result was good.


Thanks Kevin

Andy01
12-02-2019, 05:20 PM
Lol ;) Well maybe just a good idea to keep very bright stars away from the very edge of the frame, as they can detract from the main image :D
In this case either a wee crop off the top or an overall shift of the frame downwards may help :question:

Echoing what's been already said, great pic :thumbsup:
Good to see the Gums getting some astro love here :)

Geoff45
12-02-2019, 06:19 PM
Thanks Andy. I agree that I should have centralised the neb more. I quite like a few bright stars in the field, but as you say, not near the edge.

Paul Haese
22-02-2019, 11:48 PM
I did this one myself a few years back Geoff in a wider format, I am presently doing a similar scale image to what you have produced here. Last time I went fairly deep at 14 hours but might go a little deeper with the narrower field image. I really like the detail you have captured here. I am hoping for something similar myself to what you have captured.

Stevec35
24-02-2019, 11:02 AM
As others have said, a very nice image Geoff. I don't think I've seen this one before.

Cheers

Steve

Geoff45
25-02-2019, 03:06 PM
Thanks Paul. I look forward to seeing your image.

Thanks Steve. Once you stray from the usual catalogues (ngc, messier, sharpless) quite a lot of interesting objects show up

Atmos
26-02-2019, 09:36 PM
You've got yourself a really nice result there Geoff. Very clean for 4.8 hours exposure and possibly one of the shortest I've seen you use in a long time!

Geoff45
27-02-2019, 11:25 AM
Thanks Colin. Too many clouds=short exposure.

topheart
02-03-2019, 06:39 PM
Very nice!
Cheers,
Tim