Orpington Astronomical Society

Astronomy => Astrophotography => Topic started by: The Thing on Jul 06, 2011, 09:03:11

Title: Gamma Cygni Rother Valley DSC 2 July 2011
Post by: The Thing on Jul 06, 2011, 09:03:11
HEQ5 Pro, EQMOD, CdC, LX90 8" UHTC Baader Alan Gee II Telecompressor at correct spacing, Canon 350Da, Astronomik CLS-CCD clip filter, Lakeside ASCOM Focuser, Bahtinov Mask, Dunc's Collimation Mask, Meade 8x50 FinderGuidescope & QHY5, PHD Guiding, APT Astro Photography Tool.

Processed in DSS and tweaked in PS. 10x600s Lights, 10 darks, master bias and master flat from a previous image.

Full frame resampled to 1024 X 665  with sharpening. Full Size here (6Mb). (http://www.ancientlight.amateur-astronomy.org//images/Gamma-Cycnus-20110702-DSS-PS-Full.jpg)

(http://www.ancientlight.amateur-astronomy.org//images/Gamma-Cycnus-20110702-DSS-PS.jpg)
Title: Re: Gamma Cygni Rother Valley DSC 2 July 2011
Post by: Fay on Jul 06, 2011, 11:42:32
10x600 eh? You are well and truly on your way Duncan, great!



Fay
Title: Re: Gamma Cygni Rother Valley DSC 2 July 2011
Post by: JohnP on Jul 06, 2011, 11:46:04
Hi Dunc,

I reckon you forgot a few things on your equipment list there  ;)

As Fay said image looking very nice - still looks like you have a few issues with odd shaped stars on the full size but focus, processing looks spot on.

Very good,  John.
Title: Re: Gamma Cygni Rother Valley DSC 2 July 2011
Post by: Fay on Jul 06, 2011, 11:47:41
Yes, I thought there was a lot of equipment!!!!!
Title: Re: Gamma Cygni Rother Valley DSC 2 July 2011
Post by: The Thing on Jul 06, 2011, 13:28:46
There is always a lot of equipment! Most of you just don't list all of it. That's why we spend the first few hours at a DSC drinking setting up.
Title: Re: Gamma Cygni Rother Valley DSC 2 July 2011
Post by: Carole on Jul 06, 2011, 13:37:29
Some very nice data there Duncan.
Hope you don't mind a did a few tweaks to your Jpeg.
I got rid of most of the gradient, and lifted the colour of the nebulosity slightly
A very nice image

(http://www.caroleastronomy.webspace.virginmedia.com/_wp_generated/wpa1b47d8d_0f.jpg)

Carole
Title: Re: Gamma Cygni Rother Valley DSC 2 July 2011
Post by: JohnP on Jul 06, 2011, 13:56:46
QuoteI got rid of the gradient, reduced the sky background and lifted the colour of the nebulosity
... and added some noise  :lol:

Title: Re: Gamma Cygni Rother Valley DSC 2 July 2011
Post by: Carole on Jul 06, 2011, 13:58:35
You can't add noise, only reveal it.  I think you picked up my post between revising the image John as I didn't like it myself when I had posted it the first time.   

Carole
Title: Re: Gamma Cygni Rother Valley DSC 2 July 2011
Post by: JohnP on Jul 06, 2011, 15:49:37
QuoteYou can't add noise

I think you'll find you can - Photoshop has a filter especially for doing this  :lol: I always add noise to my images I dont like them if they are too smooth.... I prefer to add Gaussian noise but ocassionally use the uniform noise filter as well depending on what I am imaging... :lol: :lol: :lol:

Your reprocess does look a bit better now compared to the original - it's always tough reprocessing when you only have a jpeg to work from.

John.
Title: Re: Gamma Cygni Rother Valley DSC 2 July 2011
Post by: mickw on Jul 06, 2011, 16:35:38
Prefer Duncan's original
Title: Re: Gamma Cygni Rother Valley DSC 2 July 2011
Post by: The Thing on Jul 06, 2011, 16:43:10
Thanks Mick. I like my images pretty much as they come. I would like to know how to remove a gradient though, must look it up on the web.
Title: Re: Gamma Cygni Rother Valley DSC 2 July 2011
Post by: JohnP on Jul 06, 2011, 20:44:17
QuotePrefer Duncan's original

moi aussi !
Title: Re: Gamma Cygni Rother Valley DSC 2 July 2011
Post by: Fay on Jul 06, 2011, 20:49:52
Et moi!
Title: Re: Gamma Cygni Rother Valley DSC 2 July 2011
Post by: RobertM on Jul 06, 2011, 21:00:22
You're flying now Duncan  8)

There are bits I like about both you've posted.  Lots more nebulosity in the second but the stars have suffered, the artifact has brightened and there's more noise.

Regarding gradient removal - if you have maximdl then 'auto remove gradient' works a treat also the Gradient Xterminator PS plugin works wonders.

Robert
Title: Re: Gamma Cygni Rother Valley DSC 2 July 2011
Post by: MarkS on Jul 06, 2011, 21:36:03
Very nice Duncan!!

You've done a good job of processing - but there is still a gradient to be removed.
The stars look round - so your guiding was fine.
Towards the corners they are dagger shaped - it's about the best you will get with the Alan Gee.  But it looks pretty symmetrical so I think you've got the collimation and the seating of the Alan Gee just about right.

By the way - there's a very interesting artifact below the bright star.

Well done - they'll be no stopping you now.

Mark