Orpington Astronomical Society

Astronomy => Astrophotography => Topic started by: JohnP on Feb 11, 2008, 14:29:52

Title: NGC2244 - Cone Nebula..
Post by: JohnP on Feb 11, 2008, 14:29:52
I was in two minds as to whether to post this..? I took it last night but although it was clear it was a bit misty.. I've also since discovered this is actually quite a difficult object to image so I should have probably saved it for DSC rather than downtown Bromley.

Anyway here it is in all its glory... (not...!) I'm not happy as it's very noisy (& red)...comments welcome

Cheers,  John

(http://homepage.ntlworld.com/john.punnett/graphics/oas/cone2-resize.jpg)
Title: Re: NGC2244 - Cone Nebula..
Post by: Tony G on Feb 11, 2008, 15:00:05
John,

It's very noisy and red, isn't it. :)

Tony G
Title: Re: NGC2244 - Cone Nebula..
Post by: Ian on Feb 11, 2008, 15:08:27
That doesn't look too shabby at all John. Are you planning on getting more data tonight?

I was wondering about having a pop at this one this evening.

I had quite a good night last night, finally getting some of my equipment operation woes sorted. Nowt wrong with the kit. Errors located between keyboard and observing chair.

Title: Re: NGC2244 - Cone Nebula..
Post by: Daniel on Feb 11, 2008, 15:11:23
I think the image is great, I'd be well chuffed if i got something even close to it, i seem to have problems picking up any red in my photo's, would a Ha filter help with that at all?
Title: Re: NGC2244 - Cone Nebula..
Post by: Mike on Feb 11, 2008, 15:43:31
Very nice image and very tight FOV. What kit did you use?
Title: Re: NGC2244 - Cone Nebula..
Post by: JohnP on Feb 11, 2008, 15:53:34
Cheers Mike - I still don't like it. I used my Atik 16ic with my MN56 + Ha filter - It was a lot of data - approx 30 X 4min subs + 20mins each for R,G & B... I think local seeing last night had a lot to do with it. I've seen some brilliant images of this & mine doesn't come close.....

John
Title: Re: NGC2244 - Cone Nebula..
Post by: Mike on Feb 11, 2008, 17:12:45
It's still good. I agree, the noise looks like the sky was a bit milky maybe?
Title: Re: NGC2244 - Cone Nebula..
Post by: Fay on Feb 11, 2008, 20:55:45
I'm trying to think what this nebula reminds me of!
Title: Re: NGC2244 - Cone Nebula..
Post by: Ian on Feb 11, 2008, 22:07:58
I think it looks like a hand, thumb uppermost reaching for the bright star.

What do you think it looks like then fay?
Title: Re: NGC2244 - Cone Nebula..
Post by: MarkS on Feb 11, 2008, 23:46:09

John, I like it.  It is quite noisy though.  Wonder what the surface brightness is?

Daniel,  you have the same problem as me - the Canon is just not sensistive to H-alpha.  This does cause problems with nebulae.  The reason is that the standard infra-red filter in front of the CCD also cuts out 75-80% of the H-alpha.  You can get the filter changed http://www.astronomiser.co.uk/eosmod.htm (http://www.astronomiser.co.uk/eosmod.htm) but I wouldn't do so if you also use the camera for everyday use as well as astronomy because it affects the colour balance.  My secondhand Canon EOS300D is dedicated to astronomy but I still haven't done it - but I will get around to it sometime ...
Title: Re: NGC2244 - Cone Nebula..
Post by: JohnP on Feb 12, 2008, 09:45:14
Cheers Mark - I put it down to seeing as total exposure was actually the longest image I have ever taken... It was kinda misty...

I'm not sure about surface brightness but I suspect it is quite low as it's a very large object.

Cheers,  John
Title: Re: NGC2244 - Cone Nebula..
Post by: Mike on Feb 12, 2008, 09:52:54
If it was 'kinda misty' then that would explain the grainyness of the image.
Title: Re: NGC2244 - Cone Nebula..
Post by: Daniel on Feb 12, 2008, 13:02:26
Hi Mark, Just looked into the Astronomiser website and decided to give the guy a call, he says that with custom white balancing or a seperate IR filter on the lens, there wouldn't be any noticable difference after modification, sounds like this may be the way to go!

:O)