Blue Smoke on Putuo
Smoke can appear blue if the smoke particles are small and well lit in front of a dark background. This incense basin in a Buddhistic monastry nicely shows the effect. Nikon D90, clipped and compressed, but otherwise unprocessed picture.
Below: Joss sticks - in this case the conditions are not suited to colour the smoke blue. The contrast is too low and the lighting is not sufficient.
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