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Old 20-08-2009, 11:21 AM
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gregbradley
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Join Date: Feb 2006
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Quote:
Originally Posted by marc4darkskies View Post
The repro is much nicer but Greg, you should never normalise your R, G & B data! Normalising is really only meant to be done for mono subs within each channel, not across channels. If you do it between the R,G, and B components you may normalise a part of the image that is supposed to have a colour differential - pretty certain for this subject. The effect will be to subdue or remove colour in parts of the image. You should combine the RG & B as is and subsequently adjust any colour imbalance.

Cheers, Marcus
Thanks Marcus.
Yes I can see that, normalise puts the values in an image into the same range and as you point out different colours would have different values in some areas of the image where a particular colour is stronger than the others.

I instead used auto on DDP in CCDstack to make the subs more the same range for each channel. Then I did combine. This works pretty well although it may be better to manually do the DDP and set it to where they all look about the same brightness as auto can black clip a tad.

I redid the image and the colours came out better again.

So its a repro of a repro! Same link.

http://jjd.pbase.com/gregbradley/image/116221266/large

Greg.
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