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M1 Crab Nebula in Narrowband and Broadband, pushing the limits of mount, camera, and sky...

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Sometime last year after completing a long session on the Crab Nebula, I turned my C9.25 to it and took a 20 minute Ha exposure at F10. The little bit of detail that came through made a big impression on me, and so I planned a kit upgrade to get a proper image done at that scale.

One C11 EdgeHD and Atik428ex later, here's the result.

My EQ6 is working at its limit, but performing admirably under the pressure of providing a stable platform for a rig running at 2800mm focal length. The resolution is really pushing it too, 0.67 arcsec/pixel, but I wanted to see what the scope could do, so any time there was a clear hour or two, another few subs were added to the total mix.

I've really enjoyed this one, it has kind of made up for a dreadful year of weather and cloudy skies. I have a new reducer on the way for the scope, and possibly a new camera too, so will be looking for some new challenges in 2013.

Full details below, thanks for looking.



Full Size Here


Telescope: C11 EdgeHD

Focal Length: 2800mm

F Ratio: F10

Camera: Atik 428ex

Binned: 2x2

Resolution: 0.67 arcsec/pixel

Mount: EQ6

Exposure Details:

Luminance : 38mins

Red: 58mins

Green: 104mins

Blue: 45mins

Ha 7nm: 360mins

Oiii: 785mins

Sii: 325mins

Total Exposure: 23hrs

Data gathered over several weeks Autumn/Winter 2012


Capture: Nebulosity 3

Guiding: PHD

Stacking & Calibration: DeepSkyStacker (3x Drizzle)

Initial Processing: Pixinsight

Combining: Registar 1.0

Processing: Photoshop CS5

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Tim, that is amazing, and imaged at such a high focal length, be extremely proud of that image

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This is absolutely stunning. Gives me something to aspire to and something to keep me motivated despite the poor weather this year.

Thanks for posting!

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WOW!! Wonderful - such terrific detail - lovely :)

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That is a seriously good image! You must be proud of it and worth every penny and hour taken to get it.

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An amazing image, the detail is stunning. It always amazes me what people can achieve from their back gardens, well done.

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Pushing the eq6 to unbelievable performance !

great image !



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An incredible image of the crab Tim, the high res,version as a lovely 3D look about it. Excellent high focal length work!

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Great stuff. Proves you can image with long focal lengths on an EQ6 - with a considerable amount of skill.

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Oh, I guess that's OK... nah, just joking, that's a stonking image Tim... :)


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Wouldn't it be nice to be able to make positive suggestions on how to improve on that. All I can think of is to upgrade to an HST !!

Fantastic Tim.


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Very good image Tim. Hubble-esque and remarkable considering it is through UK skies and at such a high focal length.

Thanks for sharing! Very envyous ;)

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