Wednesday, November 19, 2008

M31: Second Attempt

So, below is my second attempt at M31. Better than the first one, methinks. Taken through fairly light-polluted skies so I fear a fair bit of the nebulosity has been washed away. I retook my flat images tonight at dusk. I pointed the WO66 at the sky with a white t-shirt and took about 20 .3 second exposures. This resulted in flat frames which did a better job of representing the optical and CCD deficiencies of the DSLR and WO66 scope.

Image Details:
  • 20 * 3 minute light exposures @ ISO800
  • 3 * 3 minute dark frames
  • 20 * .3 second flat frames
  • 20 * 1/4000 bias frames
  • Nikon D40
  • William Optics 66mm Refractor piggybacked atop a Meade 8" LX200 SCT with Milburn equatorial wedge
  • Processed in Deep Sky Stacker
  • Additional saturation and sharpening in Photoshop
















Below is a slightly modified (auto levels in GIMP) version of the same picture, revealing more of the galaxy's disc:






7 comments:

Polaris B said...

Is this image cropped out a larger one at all? I don't know how large the D40's chip is, but I do not see much coma for such a wide view. Looks like a nice setup.

Phil said...

Hey there,

Actually, not cropped!!! The D40 with my William Optics 40mm gives me quite a nice field of view with a very flat field of view.

Cheers,
Phil

Phil said...

Correction, I meant to say William Optics 66mm, not 40mm!

Ewan Bryce said...

A nice capture Phil. Very nice indeed.

Phil said...

Appreciate it, Ewan! Cheers.

Phil said...

By the way, Ewan - I have been enjoying your sketches. That's quite a talent!

I haven't been able to post on your blog as I think membership is required???

Cheers,
Phil

Ewan Bryce said...

Thanks Phil, really appreciate that! Always been interested in sketching my obs but only just started to actually do it.

The WordPress software only allows a user to comment once they register. There are different roles that I can set for a registered user such as subscribers to contributors as well as authors and editors. In this way the blog becomes a platform for the exchange and collaboration of content.

So if for example you were given the role of an author, you could actually write your own post on the Space Jockey blog.

Cheers,

Ewan