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Thanks beren for the information, I will check the link out and start my learning curve.
Joe, I will have a look at work and see if I can find some appropriate references and post them back here. Atmospheric effects are the bane of most terrestrial remote sensing researchers and while I’ve got a pretty good handle on it, most of the modern techniques use atmospheric models that measure atmospheric attenuation in specific parts of the electromagnetic spectrum that lie outside of human vision (and thus not RGB cameras), which are used to reduce its effect across all wavelengths. Unfortunately, we don’t have these wavelengths to use, so I will have a think about some earlier but very simple and useful techniques that may be of some use for RGB imagery and find some appropriate references – albeit earth observation based. One approach for instance is that blue wavelengths scatter in the atmosphere to the 4th power more than red (or something like that) so the overall ‘brightness’ of each image band could be adjusted relative to this value. Also, the angle between the declination of the celestial object and the zenith of your position is highly correlated with the amount of atmospheric influence; this could also be adjusted for. In the end this may all be academic as the brightness adjustments that everyone seems to be applying to their imagery is kind of doing the same thing, but applying objective corrections might (might!) be more realistic. I am starting to dribble on so I will go and try and find some references for you.
Cheers, nix
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