Thread: Rcw96-97-98
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Old 18-06-2015, 08:56 AM
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Paul Haese
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Quote:
Originally Posted by jase View Post
Cheers Paul! Star colours are certainly subjective. I don't use the star colours from a Ha+RGB blend alone as I find there is normally a colour shift due to the Ha. Base RGB stars are best. The rings you note around stars in the nebs are not due to sharpening. I don't use deconvolution with data from this system. Sampling is ample and with so many stars in the field deconvolution often mottles the background. I suspect what you are seeing is the stellar profile itself. On closer inspection, you'll probably find the ring is in fact colored which further confirms its the stellar profile not a processing artefact. Bringing in the RGB stars in lighten mode on a [Ha+R]GB blend can sometimes show what appears to be a star ringing effect. Its not often a smooth transition between star and neb occurs. Altering the RGB layer opacity can sometimes work. You've given me some ideas though. A star mask with a mild blur may soften the transition. I think this would need to be applied in two or three layers as the first mask would likely be a global change impacting the entire image so an iterative approach would be needed. May consider investigating this next time. Not going back for a repro on this one! Thanks for the great feedback.
Definitely star profile related and was not suggesting it was decon related. The star profile of the Ha is a lot smaller than the RGB star set. I have seen this before myself with some of my images. I found that doing a final RGB wash as you suggest with either lighten mode or screen mode works best to remove the problem. Looking forward to your next image.
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