The apparent contrast of objects lying on the surface of the earth, when observed in the visible spectrum from above the earth’s atmosphere, is calculated for three model atmospheres. The earth is illuminated by sunlight, and light is reflected from the earth’s surface according to Lambert’s law. The apparent contrast increases with increasing wavelength. The apparent contrast is lower when aerosols are in the atmosphere, than when the atmosphere is free of aerosols. The apparent contrast can be enhanced significantly, if the albedo of the object space is low, when an analyzer, such as a piece of Polaroid, is used in the optical system of the receiver.
ROBERT S. FRASER, "Apparent Contrast of Objects on the Earth’s Surface as Seen from above the Earth’s Atmosphere," J. Opt. Soc. Am. 54, 289-300 (1964)