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Problem with color separation / rainbow stars

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#1 RealSorin


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Posted 23 March 2013 - 11:08 AM

I took my 6" SCT out last night and captured some shots of PanSTARRS. Unfortunately I'm noticing this color separation / rainbow effect on the comet and the one star in the top-right of the image. (this was consistent with all the stars in the image.) This was consistent across all the frames I captured, but became more pronounced with longer exposures. Since I'm pointing so close to the horizon, I'm wondering if this might just be an atmospheric effect?

Posted Image
PanSTARRS Color Separation by SoggyAstro, on Flickr

This is with my Canon T3i in prime focus and with the scope tracking on a CG5 mount. That particular image is a crop from a single 30 sec exposure.


#2 JoseBorrero



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Posted 23 March 2013 - 12:30 PM

you can rearrange RGB in registax

#3 RealSorin


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Posted 25 March 2013 - 01:35 PM

Thanks, but I have a Mac, so can't use Registax. I'm assuming this is an atmospheric aberration; any other suggestions for how to correct the image?

#4 mellowgeorge


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Posted 25 March 2013 - 01:43 PM

Could it be chromatic aberration?

#5 rigel123


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Posted 25 March 2013 - 03:04 PM

It's more than likely that it is atmospheric induced and you might be out of collimation a bit. Photoshop also has a method to line up the colors if they are shifted like that.

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