Orpington Astronomical Society

Astronomy => Astrophotography => Topic started by: RobertM on Aug 12, 2009, 22:11:02

Title: NGC6960 the Witches Broom in false colour
Post by: RobertM on Aug 12, 2009, 22:11:02
This nebula is the western part of the Veil supernova remnant in Cygnus; it exploded about 6,000 years ago and is somewhere in the region of 2,000 light years away.  The entire network of filaments of the whole nebula covers an area roughly equivalent to 30 times the area of the full moon.

Usual culprits were used to take this image: Starlight Xpress SXV-H9 camera, Takahashi Sky90 refractor at f/4.5.  Ionised elements were mapped as Red representing Ha, Green OIII and Blue SII; 11 exposures of 600 seconds through each filter.

This was unfinished business from the last clear night that I could image on (16th July).   Unfortunately the subs didn't quite line up properly due to rotation and the Moon was too close giving high background counts.  Yes it does have the Astronomik Halos which I tried to process out - need to learn more PhotoShop!

Any comments gratefully received:

(http://farm3.static.flickr.com/2533/3815932552_b9c06edb83_o.jpg)
Title: Re: NGC6960 the Witches Broom in false colour
Post by: Fay on Aug 13, 2009, 08:11:25
That's nice, Robert, I have left my camera in position as I would like to try my OIII SII filters. At least you have a lot of information collected, so you can process more at your leisure until you are happy. Is that your first OIII, SII image?

As we have not been outside for a long time, it is hard to remember all the processing twists and turns.
Title: Re: NGC6960 the Witches Broom in false colour
Post by: RobertM on Aug 13, 2009, 09:05:27
Thanks Fay, Yes it's my first with the SII filter as well.   The Sulphur line is quite weak on this one, the strongest by far is OIII.

Needs brightening up a bit!
Title: Re: NGC6960 the Witches Broom in false colour
Post by: JohnP on Aug 13, 2009, 10:17:15
Nice Robert - tons of wispy detail... The colours are very saturated (is that normal for this type of processing).

John
Title: Re: NGC6960 the Witches Broom in false colour
Post by: RobertM on Aug 13, 2009, 10:46:52
QuoteThe colours are very saturated (is that normal for this type of processing).

Hmmm... Interesting and thanks for pointing that out.  This is my first real attempt in integrating the SII data so for now I think I'll just put it down to ignorance in processing.  I'll give it another go in a weeks time when I get back.

Thanks
Robert 
Title: Re: NGC6960 the Witches Broom in false colour
Post by: JohnP on Aug 13, 2009, 11:24:09
So I guess you'll be missing DSC... :-(

Have a good time..

John
Title: Re: NGC6960 the Witches Broom in false colour
Post by: RobertM on Aug 13, 2009, 11:50:21
Yes John, infortunately I will miss it.  I'll take some kit with me but there won't be much room between the cases  :(

Hope the DSC goes well and you get some good weather !

Title: Re: NGC6960 the Witches Broom in false colour
Post by: Rocket Pooch on Aug 13, 2009, 12:41:02
Nice one Rob, I might have another go at that soon :-)

I'm away with my kit this weekend and next weeked at DSC and the Caravan is fixed ahead of schedule yay!
Title: Re: NGC6960 the Witches Broom in false colour
Post by: Fay on Aug 13, 2009, 12:52:04
What caravan, Chris....new one?
Title: Re: NGC6960 the Witches Broom in false colour
Post by: Rocket Pooch on Aug 13, 2009, 18:47:28
Nope got the old one fixed up a bit, probably bring it along for the weekend.
Title: Re: NGC6960 the Witches Broom in false colour
Post by: Ian on Aug 14, 2009, 09:53:27
I'll be looking out for you on "Pimp My Pikey". Did you get that bubble-filled hot tub put in?
Title: Re: NGC6960 the Witches Broom in false colour
Post by: MarkS on Aug 14, 2009, 23:30:05

Nice one Robert.  Lots of detail there and good sharp stars as always!

How do you know the halos are caused by the filters?

Mark
Title: Re: NGC6960 the Witches Broom in false colour
Post by: Fay on Aug 15, 2009, 08:33:26
Well, Chris, at least we still have the wind break come light diffuser that is the pikey
Title: Re: NGC6960 the Witches Broom in false colour
Post by: RobertM on Aug 15, 2009, 09:52:16
Mark, Someone did a test against another well known German make and concluded that the anti reflective coatings were inferior and cause halos on bright stars.   Astronomik of course deny there is a problem but I have heard there are improved filters on the way.  I had to process out three halos on the Ha channel in this image !
Title: Re: NGC6960 the Witches Broom in false colour
Post by: Daniel on Aug 16, 2009, 13:30:40
Gorgeous image Robert, looking really whispy, and your stars are pin sharp across the board!

Daniel
:O)