Ptolemy's Cluster - Messier 7

[SkyViking (Rolf)]

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 (Rick)]

Lovely the way the stars just float there, Rolf!

[strongmanmike (Michael)]

Well, lucky you did process this one, it's a fine image

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

Mike

[Nico13 (Ken)]

Nice capture Rolf, I like that area of sky full of interesting stuff

[alpal]

Nice shot - I can just make out the diffraction spikes.

[John Hothersall]

That is a very beautiful result, the power of the UV in those stars can be felt.

Superb, JohnH

[Paul Haese]

Hey Rolf that is a really nice image. Great colour saturation and the cluster really stands out. Lovely work.

[multiweb (Marc)]

Top shot Rolf. Very nice close up.

[iceman (Mike)]

stunning! Love the blues amongst the red and gold.

[gregbradley]

Very striking Rolf.

Greg.

[Dennis]

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 (Troy)]

Lovely colour and pop. Really like it.

[RB (Andrew)]

Beautiful !
Love those blue hues, visually mesmerising !!

[marco (Marco Lorenzi)]

Very nice Rolf, the color contrasts are striking and add lots of beauty to this image!
Clear skies
Marco

[marc4darkskies (Marcus)]

Almost didn't process it?!

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

Cheers, Marcus

[Ross G]

A great photo Rolf.

The stars are amazing!


Ross.

[iceman (Mike)]

Congrats for the showcase on Universe Today, Rolf!

http://www.universetoday.com/96744/a...by-sky-viking/

[ourkind (Carlos)]

Originally Posted by iceman

Congrats for the showcase on Universe Today, Rolf!

http://www.universetoday.com/96744/a...by-sky-viking/

Congratulations Rolf!

[SkyViking (Rolf)]

Originally Posted by RickS

Lovely the way the stars just float there, Rolf!

Thank you Rick

Originally Posted by strongmanmike

Well, lucky you did process this one, it's a fine image

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

Mike

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.

Originally Posted by Nico13

Nice capture Rolf, I like that area of sky full of interesting stuff

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

Originally Posted by alpal

Nice shot - I can just make out the diffraction spikes.

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.

Originally Posted by John Hothersall

That is a very beautiful result, the power of the UV in those stars can be felt.

Superb, JohnH

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

Originally Posted by Paul Haese

Hey Rolf that is a really nice image. Great colour saturation and the cluster really stands out. Lovely work.

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

Originally Posted by multiweb

Top shot Rolf. Very nice close up.

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

Originally Posted by iceman

stunning! Love the blues amongst the red and gold.

Thank you Mike, glad you enjoyed it

Originally Posted by gregbradley

Very striking Rolf.

Greg.

Thanks Greg

Originally Posted by Dennis

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

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.

Originally Posted by troypiggo

Lovely colour and pop. Really like it.

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

Originally Posted by RB

Beautiful !
Love those blue hues, visually mesmerising !!

Thanks Andrew

Originally Posted by marco

Very nice Rolf, the color contrasts are striking and add lots of beauty to this image!
Clear skies
Marco

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

Originally Posted by marc4darkskies

Almost didn't process it?!

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

Cheers, Marcus

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

Originally Posted by Ross G

A great photo Rolf.

The stars are amazing!


Ross.

Thank you Ross

Originally Posted by iceman

Congrats for the showcase on Universe Today, Rolf!

http://www.universetoday.com/96744/a...by-sky-viking/

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

Originally Posted by ourkind

Congratulations Rolf!

Thanks Carlos!