Atmospheric Haze

a uniform luminous fog that obscures distant parts of the landscape; it is caused by the scattering of light rays in the layer of air between the observer and the objects being viewed. In clear air light rays of the blue-violet part of the spectrum are scattered more intensely than are rays of yellow and red, since the atmospheric haze, as well as distant dark objects, acquires a bluish coloration (the “blue distance”).

Atmospheric haze smoothes out differences in brightness and color of distant objects and thereby reduces their visibility, to the point of complete disappearance. Techniques for weakening the effect of atmospheric haze have been developed to the greatest extent in aerial photography. They are based on the transfer of the photography (that is, the use of appropriate aerial films and light filters) to the yellow, red, and near-infrared part of the spectrum, where atmospheric haze is not as bright. When atmospheric haze is caused by scattering on large particles of dust or fog, such methods are not effective, because in these cases scattering is uniform throughout all parts of the spectrum.