Orpington Astronomical Society

Astronomy => Astrophotography => Topic started by: RobertM on Aug 29, 2008, 19:10:31

Title: Chompa Chompa Chompa ... well ok NGC281
Post by: RobertM on Aug 29, 2008, 19:10:31
I know, not a very good pacman impression ...

Pacman Nebula NGC281 from 24th Aug.

Posted via Flickr, 90 minutes Ha in 5 min subs with the Sky 90 and SXV-H9/Astronomik 13nm Ha filter.

(http://farm4.static.flickr.com/3215/2809405970_a4e11d6ae5_b.jpg)

Other sizes here : http://www.flickr.com/photos/29673723@N04/2809405970/sizes/l/ (http://www.flickr.com/photos/29673723@N04/2809405970/sizes/l/)
Title: Re: Chompa Chompa Chompa ... well ok NGC281
Post by: Daniel on Aug 29, 2008, 19:51:33
Damn, not working! :(
Title: Re: Chompa Chompa Chompa ... well ok NGC281
Post by: JohnP on Aug 29, 2008, 21:20:15
Robert that looks a lot better - looks like you brightened up the neb...

that's a great shot again - can't believe resultrs you are getting unguided....

John
Title: Re: Chompa Chompa Chompa ... well ok NGC281
Post by: Daniel on Aug 29, 2008, 21:46:10
Fantastic! was this taken somewhere really dark? the contrast is lovely!
Title: Re: Chompa Chompa Chompa ... well ok NGC281
Post by: RobertM on Aug 29, 2008, 22:16:44
Taken from sunny downtown Orpington so no not a dark site and there was high cloud but you have to take it when you can get it !
Title: Re: Chompa Chompa Chompa ... well ok NGC281
Post by: Daniel on Aug 29, 2008, 23:16:22
That's just amazing then, love how flat the field is all the way across
Title: Re: Chompa Chompa Chompa ... well ok NGC281
Post by: Fay on Aug 30, 2008, 07:52:12
Yes, you are getting some really good images, Robert. Such short subs as well.
I like this one, had not noticed it is quite a nice subject, before.

Must try it out.

Fay
Title: Re: Chompa Chompa Chompa ... well ok NGC281
Post by: RobertM on Aug 30, 2008, 09:43:01
Fay, Shorter subs = less problems and since I nearly always catch a 747 before midnight it helps.  Also with the subjects being nearer the pole PA is not so critical so I can get away with unguided.  Both Cepheus and Cassiopea have some really lovely nebulae and now is a good time ... might try another one with the DSLR tonight - clear did you say ?  Mind you, your record recently is worse than the BBC so I'm not holding out much hope :( 
Title: Re: Chompa Chompa Chompa ... well ok NGC281
Post by: Fay on Aug 30, 2008, 14:56:04
Is there a certain instance when you use OIII filter? Or do you use it when you fancy?
Title: Re: Chompa Chompa Chompa ... well ok NGC281
Post by: RobertM on Aug 30, 2008, 15:39:26
Fay, I have never used an OIII filter but most if not all emission nebulae emit some light due to ionized Oxygen.  The band is generally not as bright as Ha - Hydrogen is the most abundant element in the universe so there's more of it about to be ionized.  I would say in answer that you need to give it a try on something you know has strong OIII emissions.  The Pacman nebula will be my first attempt.

Hope that helps
Title: Re: Chompa Chompa Chompa ... well ok NGC281
Post by: MarkS on Sep 03, 2008, 22:02:49
Nice one Robert!
Title: Re: Chompa Chompa Chompa ... well ok NGC281
Post by: RobertM on Sep 12, 2008, 08:03:23
Took 80 minutes of OIII and synthesised the green channel with Ha using Noels tools.  This is my first attempt with the OIII filter and didn't get the camera lined up between nights - doh !  Will also have to do some extra noise processing and it's going to need a whole lot more subs...

18 x 5 min Ha unguided
8 x 10 min OIII guided

Ha -> Red
OIII -> Blue
Synthesised -> Green

(http://gallery.orpington-astronomy.org.uk/albums/userpics/10031/NGC281HaSiOIII.jpg)

Title: Re: Chompa Chompa Chompa ... well ok NGC281
Post by: MarkS on Sep 12, 2008, 08:30:55

Robert,

That is looking very good.  The detail is excellent, there are some lovely variations in nebulosity and the "guiding" is spot on.  Very nicely processed.

Mark
Title: Re: Chompa Chompa Chompa ... well ok NGC281
Post by: JohnP on Sep 12, 2008, 08:47:32
Quoteand the "guiding" is spot on

Mark believe it or not I don't think Robert guides????

Robert - that image is looking fantastic - that is one of the best Pacman neb's I have seen - the colours are fantastic - not too 'overpowering' - All I can say is very expertly processed...

John
Title: Re: Chompa Chompa Chompa ... well ok NGC281
Post by: MarkS on Sep 12, 2008, 10:01:46
Quote from: JohnP
Mark believe it or not I don't think Robert guides????

That's why I put "guiding" in quotes ...
Title: Re: Chompa Chompa Chompa ... well ok NGC281
Post by: RobertM on Sep 12, 2008, 10:11:41
Thanks for the comments but I still have some way to go till I'm happy with this one.

Yes, I did actually guide the 10 minute subs as I've now got a guide scope to go with that 16IC :) though I'm not sure it made that much difference.  FWHM was about the same in both cases though I got the focusing closer with the OIII.  Going to try a new focusing mask next time and see if that improves things.

If I can resist the urge to go for another target I'll try and get a few more hours signal - OIII is not very strong so needs a lot of subs and the Ha needs a lot more to bring out the faint detail.
Title: Re: Chompa Chompa Chompa ... well ok NGC281
Post by: JohnP on Sep 12, 2008, 10:12:41
Sorry Mark.... I misunderstood your "quotes".... John
Title: Re: Chompa Chompa Chompa ... well ok NGC281
Post by: JohnP on Sep 12, 2008, 10:14:00
QuoteI did actually guide the 10 minute subs

Wrong again ... :-( think I'll shut up........

John
Title: Re: Chompa Chompa Chompa ... well ok NGC281
Post by: Fay on Sep 13, 2008, 07:29:05
Very nice Robert. What does a pacman look like?
Title: Re: Chompa Chompa Chompa ... well ok NGC281
Post by: Rocket Pooch on Sep 13, 2008, 08:27:04
Fay do you not know what one is!!!!!  Well what can I say, honest, what you like, crikey, blimey etc.. 

Rob, nice image.
Title: Re: Chompa Chompa Chompa ... well ok NGC281
Post by: Fay on Sep 13, 2008, 08:41:47
Ok I have just had a look & now know what it is.

I am sure that a similar motif used to be on clothing tags...........a while ago. I remember they were on my vests!!!!
Title: Re: Chompa Chompa Chompa ... well ok NGC281
Post by: RobertM on Sep 13, 2008, 10:35:09
Looks like it's going to be the Canon for a while as the H9 has packed up.  Having some trouble with the USB hub so restarted it using the power lead now all I get is diagonal lines.  I'll try reflashing the bios if I can find the procedure anywhere as this was a previous fault otherwise it's off to SX again :(
Title: Re: Chompa Chompa Chompa ... well ok NGC281
Post by: Rocket Pooch on Sep 13, 2008, 11:09:48
hmm wait a while and the 8.6mpix mono's will be here then sell it and get one of those!

http://www.kodak.com/global/en/business/ISS/Products/Fullframe/KAF-8300/overview.jhtml?pq-path=11937/11938/12138/12239
Title: Re: Chompa Chompa Chompa ... well ok NGC281
Post by: RobertM on Sep 13, 2008, 13:53:56
Yep, my thoughts exactly depending on the price.
Title: Re: Chompa Chompa Chompa ... well ok NGC281
Post by: RobertM on Sep 13, 2008, 20:15:55
SXV-H9 now fixed thanks to Terry at SX...
Title: Re: Chompa Chompa Chompa ... well ok NGC281
Post by: Rocket Pooch on Sep 14, 2008, 10:18:24
That's good news, then you and I will both have to fight over one of those KAF cameras when they come out.

After I get another mount :-)


Title: Re: Chompa Chompa Chompa ... well ok NGC281
Post by: JohnP on Sep 14, 2008, 10:23:42
QuoteAfter I get another mount

Surely you mean after you get the one that's damaged repaired.....? Or are you talking about another acquisition...?

John
Title: Re: Chompa Chompa Chompa ... well ok NGC281
Post by: Rocket Pooch on Sep 15, 2008, 07:34:23
Well, the EQ6 will be going this year and it will need a replacement.

But what will it be?
Title: Re: Chompa Chompa Chompa ... well ok NGC281
Post by: JohnP on Sep 15, 2008, 09:42:41
U still got your name on that waiting list??????
Title: Re: Chompa Chompa Chompa ... well ok NGC281
Post by: RobertM on Sep 15, 2008, 10:56:36
G41 I reckon, I thought Ian King had one of those but sold it.  The AP900's are pricey but if you did get one you'd wish you had paid a few quid more for an AP1200.  The next step up is a relatively expensive one unless you can pickup something good second hand.