Orpington Astronomical Society

Astronomy => Astrophotography => Topic started by: JohnP on Aug 21, 2012, 21:22:55

Title: Witches Broom from Bromley 19th Aug 2012
Post by: JohnP on Aug 21, 2012, 21:22:55
Took this the night after Fay grabbed her great shot from Blacklands (& after the night I took the heart Neb - Blimey 2 nights in a row - Must be some kind of record at least for me...)..

Anyway it's a tough object & needs a lot more subs & a wider FOV. Details as follows:

Atik 314L+ on ED80
Baader 7nm Ha
Off Axis Guider
30 X 5mins Exposure
No Flats, Darks or Bias's
Again a very warm muggy evening... Had swarms of mozzie's round my head.....

Thks,  John.

(http://jpastronomy.co.uk/graphics/OAS/NGC6960-Veil-30x5mins.jpg)
Title: Re: Witches Broom from Bromley 19th Aug 2012
Post by: Rocket Pooch on Aug 21, 2012, 21:37:24
:-)

Title: Re: Witches Broom from Bromley 19th Aug 2012
Post by: MarkS on Aug 22, 2012, 00:29:12

Excellent shot John.

I love the large scale of this.  Lots of detail and lots of fine filaments.
Title: Re: Witches Broom from Bromley 19th Aug 2012
Post by: Carole on Aug 22, 2012, 07:06:16
You did very well to get this all into the FOV.  Also nice to see what you can get from Bromley with an Ha filter.

Nice image John, are you going to add any colour to it?

Carole
Title: Re: Witches Broom from Bromley 19th Aug 2012
Post by: RobertM on Aug 22, 2012, 14:06:28
Nice one !  I like the care you've taken over framing to get as much in a possible as that can't have been too easy.

Robert
PS. I'm not commenting on the image till I get a decent calibrated monitor to see it on ;)
Title: Re: Witches Broom from Bromley 19th Aug 2012
Post by: Fay on Aug 22, 2012, 22:11:35
John  that is so good!!!!!! The air must be clearing around your way
Title: Re: Witches Broom from Bromley 19th Aug 2012
Post by: JohnP on Aug 22, 2012, 22:23:18
Thks all - I must admit I was surprised with result from Bromley..

Carole - Adding colour from Bromley will be tough as I don't have NB filters (O & S) - RGB is really difficult I have tried before... It may be time for me to invest in some more filters...
Robert - Had to laugh at your comment about framing - I just a 1 star alignment - then a goto & just move a tad using RA & DEC controls on handset - I didn't need to rotate - just luck that it lined up.. :-)
Fay - The 7nm Baader always amazes me - I can barely see any stars in the summer triangle from my garden yet the filter really 'cuts through all the murk...' Well worth the money.

Thks again,  John
Title: Re: Witches Broom from Bromley 19th Aug 2012
Post by: Carole on Aug 23, 2012, 09:21:21
QuoteRGB is really difficult I have tried before
John do you mean is that RGB is difficult from Bromley because of the light pollution?

Just trying to get my head around things because I am considering a larger chip CCD camera and what will be best for me.

Carole
Title: Re: Witches Broom from Bromley 19th Aug 2012
Post by: MarkS on Aug 23, 2012, 10:41:33
Quote from: Carole
QuoteRGB is really difficult I have tried before
John do you mean is that RGB is difficult from Bromley because of the light pollution?

It's an interesting question for the mono camera "community".  How do you do RGB from a light polluted location?  Or do you simply stick to narrowband?

With a colour camera, a CLS filter makes a huge difference to imaging from a light polluted place.  To get the same effect with a mono camera I suppose you could use a CLS filter simultaneously with the R, G, B filters but is this possible with a filter wheel?
Title: Re: Witches Broom from Bromley 19th Aug 2012
Post by: JohnP on Aug 23, 2012, 11:00:24
Well on the few times I have tried RGB from my garden I normally spend hours in the processing to try & get balance etc. correct. I have had to use CLS filter which really screws the balance up. I used to have a nose piece in front of my filter wheel with CLS permanently installed - then do RGB through the CLS. With the Ha it didn't matter because the BandWidth of the HA filter falls within the BW of the CLS. I always also used to get big differences in size of stars when imaging through the three different filters which then gives big issues at processing with halo's etc. but I guess that's down to quality of optics used. Anyway RGB has always been really tough..  Maybe I need to try & spend a few more sessions developing a technique..

John
Title: Re: Witches Broom from Bromley 19th Aug 2012
Post by: Tony G on Aug 23, 2012, 16:42:09
Great image John.

(if you are having trouble with the colour aspect speak to Doug as he has captured all the colours of the rainbow....litreally!)

Tony G

PS.........I prefer the Mono, ask Fay, as I think her images are stunning.
Title: Re: Witches Broom from Bromley 19th Aug 2012
Post by: JohnP on Aug 23, 2012, 20:23:12
Cheers Mr G. ;-) much appreciated... John