|MadSci Network: Physics|
Hi David, I don't think that this question has ever been studied purely in terms of physics. I know that photographers often use the term "special quality of light", and I once actually took pictures in a Californian desert. As you probably know, light can be selectively transmitted, scattered and reflected, all this in a wavelength-dependent way. Many factors can influence the relative proportions of these effects. If there is a haze in the air, a greater part of the light hitting an object is diffuse, whereas a clear sky and dry air favor hard contrasts by direct illumination. Morning and evening light has to travel longer paths through the atmosphere, and thus the filtering effect of atmospheric haze is stronger. Light can be reflected by the ground - a sandy desert will yield a different light than a city street, the sea, or snow. If pictures are taken under trees, the light has a green tint, which is often noticed only on the finished print because our eyes quickly adapt to the "color of light" in nature. If a photographer arrives for the first time in a place far from home, the quality of light is very likely to strike him as "special", because he is not used/adapted to it. But special quality of light can also be experienced at home under unusual atmospherical conditions. Best Regards Werner Sieber
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