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Old 18-08-2007, 03:55 PM
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Geoff45 (Geoff)
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Join Date: Jul 2006
Location: Sydney
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Quote:
Originally Posted by higginsdj View Post
Reflection nebula are coloured blue, emission nebular are coloured red for exactly the same reason that our sky is blue. This is not to be confused with clouds that are lit almost directly (near line of sight) by background stars.

To colour correct your image you need to find a white star (G5-G8 Spectral classification I think) and split out the RGB of the image into layres then adjust until the brightest part of the white star is white (assuming you haven't over exposed that star iun the image). There are charts online that dictate the RGB colour of all spectral types of stars so you can also use these.

Cheers
I agree that stars are the way to go. If you can identify a bright star in your field, you can probably find out its spectral class and hence its true colour. So if you fiddle till that's right, presumably everything else will also be OK.
Geoff
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