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Old 22-09-2014, 10:10 AM
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JohnH
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Join Date: Feb 2005
Location: NSW
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Quote:
Originally Posted by RickS View Post
If you look at the CCDI data you'll see that, on average, the blue subs are less bright than the red and green subs (Background).

When the subs get stretched the blue ones need to be stretched further and the blue channel stars bloat giving a blue halo. It's the same reason that Hubble palette images have magenta star halos.

Cheers,
Rick.
So I should have been exposing my B frames for longer than the Rs and Gs...any general guidance on exposure ratios to use or is it too dependent on the filter/optic/ccd combination??
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