Friday's looking good!!!

[Daniel]

Had a look on the met office website and friday looks like it may well be very clear. (looks like proper clear sky too ie, without mist)

And of course the moon will be all but gone too.

Oh, by the way, i got that C14 last week, but haven't had particularly good weather to try it out, so im now torn between trying out the C14 but maybe wasting good imaging time sorting through problems with the new setup (I've tried out the scope on the CGE already and it's now horribly overloaded)

Or, leaving the C14 in for the night and getting in some quality imaging time, probably with the 80ED for some nice widefield work.

Oh, by the way, speaking of the 80ED and it's horrible coma, I've discovered the lens correction tool in photoshop, sports out the coma a treat!

[MarkS]

Daniel,

If your C14 overloads your CGE what on earth are you going to do?

How does the coma correction work?  Do you have a before and after?

Mark

[JohnP]

Yep - I'd be interested in learning about the coma fix as well.... John

[Daniel]

The CGE seems to be coping, although it is over the weight limit now I've added the guide setup. I've actually found it more stable when running the side by side plate though rather than the C14 on it's own which is strange, although I had to buy another weight for it in this configuration and haven't tested it properly yet.

If it's too much for the CGE i'll probably keep it at the sidelines for a while until a Titan 50 or better mount comes up on one of the second hand boards.

That said, if I don't run the side by side setup im within the weight threshold, so maybe If I save up I could get a hyperstar and just not guide on it for a while.

Anyway, the coma correction is quick and dirty, It's far from perfect, but definetly helps I've dragged up my old NGC7000 I did on the 80 which had particularly bad coma, here's a before and after :-





You can find it under Filter / Distort / Lens correction, it also has tools for fixing vignetting in there although i haven't tried these yet.

[MarkS]

Yes, I can see what it's doing (Hint: load up both images and flick from one to another)

It's correcting for the lens distortion that elongates the stars towards the corners but it is not correcting for the defocusing caused by the curvature of the focal plane.  This would require a deconvolution.

So it's unable to totally remove the coma.

[Rocket Pooch]

thats impressive.