A nice image, Kevin. I'm not a fan of nuking all the green either, though I do tend to shift it somewhat towards the blues.
Some insightful posts in this thread as well
Quote:
Originally Posted by kosborn
I have some nice RGB data and would like to add RGB stars. RickS, if you happen to wander past this post, I found the following you posted on a different forum a couple of years ago:
"I usually add RGB stars to a NB image by extracting the L, a* and b* channels from each then using PixelMath and a star mask to blend the a* and b* from the RGB with the a* and b* from the NB image. Recombine the L, a* and b* for the NB image and voila! Sounds easy but there's always a bit of messing around and tuning for any specific image. The advantage of this approach is that the original NB star profiles are preserved and only the colour is changed."
Can you expand on that for a PI wannabe?
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Extracting the CIELAB from NB and RGB images is easy: ChannelExtraction. Then I normally do some PixelMath like this: "iif(star_mask>0.1,mean(NB_a,RGB_a) ,$T)" Apply to the NB a* data and this blends the data in the areas covered by the star mask (the magic 0.1 can be adjusted to tweak the star coverage - a smaller number exposes a larger area around the stars.) A similar PixelMath expression is used for b*. Recombine the L* and modified a* and b* with ChannelCombination and see how it looks. You'll probably need to redo the PixelMath a couple more times to get a stronger effect.
Cheers,
Rick.