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rogerg
07-09-2007, 11:45 PM
What would people recommend I do to get rid of this blue halo my Megrez puts on my 350D images?

I have "AstroPlugins" in photoshop, but there was another set of plugins that someone once recommended to me but I can't remember?

I normally play around with cruves, selective colour, select colour range and then curves/levels, etc etc. I'm sure there's a better way!

AstroPlugins "Chromatic Aberration" filter works well to get rid of the blue, but leaves the areas looking darker or off-colour instead, so doesn't help so much.

Ideas?

Most of my shots aren't prime focus on the Megrez, so only sometimes come up against the problem and hence have never sorted it out, until now! (attempting at least)

Oh, and the attached image is about as bad as it comes - I haven't done anything to try and reduce the effect, it's effeictively a "raw" but raw stack of 5 images.

Thanks,
Roger.

ballaratdragons
08-09-2007, 12:28 AM
Roger, this might be the one your thinking of. It has actions to get rid of Blue/Violet halos.

http://actions.home.att.net/Astronomy_Tools_For_Full_Version.ht ml

1. I ran your image through the program and here is the result.
2. And a screenshot showing what I clicked on. Yep, that easy. It took a whole 2 seconds :thumbsup:

dugnsuz
08-09-2007, 12:42 AM
That's it, spread the love brother Ken!!;)
Doug:thumbsup:

ballaratdragons
08-09-2007, 12:43 AM
:thumbsup: ;) :D :whistle:

rogerg
10-09-2007, 02:34 PM
Ken,

Thanks very much for the reply, sorry about the delay, over the weekend I forgot all about the thread to be honest! :screwy:

Looks like the thing I was looking for, that's for sure. Problem is I only have PS 5, so I think I might need to upgrade PS... hmmmm. I might bight the bullet and do that soon. :)

Ingo
10-09-2007, 03:05 PM
Wow I love you. Chromatic Abbreation no more!

iceman
10-09-2007, 03:07 PM
Wow that's horrible CA, Roger.

Nice tools from Neil.

rogerg
11-09-2007, 12:20 PM
Yeah. Never used to be a problem with film, because the colours were more balanced. But with un-modified DSLR, all the reds, yellows, greens disappear and I'm left with this wonderful blue :(

Still, very sharp images :thumbsup: