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synthetic luminance for rgb/osc

Posted: Thu Oct 03, 2019 7:53 pm
by Rkonrad
I was wondering if there is any point to loading up a standard dslr/osc image to "compose", then create a synthetic luminance derived from rgb (simply adding the same data to all the channels). Would this strengthen the luminance or is it simply redundant? I've tried it and get, I *think*, better results. The resultant stretch seems to have more detail in the shadows. Example: https://www.flickr.com/gp/rkonrad/9H6271 Thanks!

Richard

Re: synthetic luminance for rgb/osc

Posted: Fri Oct 04, 2019 5:39 am
by admin
Hi Richard,

There should be no difference, as ST processes luminance and chrominance separately for most things. The only - very important - difference is when you use a DSLR or OSC dataset that has not been white balanced. In that case StarTools will create a synthetic luminance set with 200% weighting of the green channel, as a DSLR's Bayer matrix causes the sensor to record twice the amount of green samples versus red and blue samples.
This should result in a cleaner luminance dataset, while the coloring is not affected.

That's a nice image btw!