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SkyViking
09-08-2012, 09:04 PM
Hi All,

This was really just a quick test image since the Moon was very near the target and illuminated at 78%. I almost didn't process this one as I thought it would not be worth it with the Moon so close. But we are going through a cloudy patch here in Auckland right now so I gave it a go - and interestingly didn't have any problems with gradients or any other artefacts from the bright Moonlight.

The image shows Ptolemy's Cluster, the famous bright open star cluster easily visible with the naked eye near the tail of Scorpius. It lies at a distance of 980 light years and has some 80 member stars within its diameter of about 25 light years. The age of these young bright stars is approximately 200 million years.
The cluster was known as a hazy patch in the sky already in antiquity and was first described by the ancient astronomer Ptolemy in 130 AD.

Link to large image (2.7MB): http://www.pbase.com/rolfolsen/image/145284502/original

Image details:
Date: 31st May 2012
Exposure: LRGB: 48:24:24:24m, total 2hrs @ -28C
Telescope: 10" Serrurier Truss Newtonian f/5
Camera: QSI 683wsg with Lodestar guider
Filters: Astrodon LRGB E-Series Gen 2
Taken from my observatory in Auckland, New Zealand

Hope you enjoy the view.

Regards,
Rolf

RickS
09-08-2012, 09:13 PM
Lovely the way the stars just float there, Rolf!

strongmanmike
09-08-2012, 09:22 PM
Well, lucky you did process this one, it's a fine image :thumbsup:

You look to have pretty good seeing where you are, the stars just keep on going :eyepop:

Mike

Nico13
09-08-2012, 09:51 PM
Nice capture Rolf, I like that area of sky full of interesting stuff

alpal
09-08-2012, 10:02 PM
Nice shot - I can just make out the diffraction spikes.

John Hothersall
09-08-2012, 10:04 PM
That is a very beautiful result, the power of the UV in those stars can be felt.

Superb, JohnH

Paul Haese
10-08-2012, 01:03 AM
Hey Rolf that is a really nice image. Great colour saturation and the cluster really stands out. Lovely work.

multiweb
10-08-2012, 07:54 AM
Top shot Rolf. Very nice close up. :thumbsup:

iceman
10-08-2012, 07:55 AM
stunning! Love the blues amongst the red and gold.

gregbradley
10-08-2012, 08:14 AM
Very striking Rolf.

Greg.

Dennis
10-08-2012, 12:02 PM
Lovely work Rolf – you have a real talent for presenting these well imaged objects in a different light, breathing new life into the jaded palettes of these oft imaged showpieces.

Cheers

Dennis

troypiggo
10-08-2012, 12:07 PM
Lovely colour and pop. Really like it.

RB
10-08-2012, 12:08 PM
Beautiful !
Love those blue hues, visually mesmerising !!

marco
10-08-2012, 01:00 PM
Very nice Rolf, the color contrasts are striking and add lots of beauty to this image!
Clear skies
Marco

marc4darkskies
11-08-2012, 10:20 AM
Almost didn't process it?! :screwy:;)

That's a beautiful image of a very photogenic cluster Rolf! Nice treatment of the contrasting colours - a very striking image! :thumbsup:

Cheers, Marcus

Ross G
12-08-2012, 04:42 PM
A great photo Rolf.

The stars are amazing!


Ross.

iceman
13-08-2012, 04:32 AM
Congrats for the showcase on Universe Today, Rolf!

http://www.universetoday.com/96744/astrophoto-ptolemys-cluster-by-sky-viking/

ourkind
13-08-2012, 01:17 PM
Congratulations Rolf!

SkyViking
20-08-2012, 09:46 AM
Thank you Rick :)


Thanks Mike, yeah on standard nights here the seeing is hovering just around 2" but I've seen it down at 1.7" on occasion. This depends on the focal length too though, the above is at native f/5 = 1270mm.


Thanks Ken, it's a very picturesque area for sure.


Thank you Allan. I enjoy the thin sharp diffraction spikes that the wire spider gives. They are not very pronounced in this image though due to the relatively short exposure time.


Thanks very much John, yes they are some powerful stars!


Thank you Paul, glad you liked the saturation, I worked quite a bit on that. :)


Thanks Marc, yes it's quite close, the cluster just fits in the FOV.


Thank you Mike, glad you enjoyed it :)


Thanks Greg :)


Thank you very much Dennis. Clusters are quite overlooked in my opinion, but they are stunning objects indeed. They make for good targets on moonlit nights where the deep stuff might be out of range, that's what this image was really an experiment to see.


Thank you Troy, yes this cluster pops I think thats the word! :)


Thanks Andrew :)


Thank you Marco, yes the contrast with the rich golden background makes for a nice target.


Thanks Marcus, yeah I was too pessimistic regarding the effect form the Moon :lol:, but lesson learned: Any night is good for imaging something!


Thank you Ross :)


Thanks Mike, I didn't even notice until you told me :lol:. I had just added the photo to their Flickr group and didn't know they picked it.


Thanks Carlos!