Photographs can thus be made of subjects which radiate in the near-infrared, such as stars, certain lasers and light-emitting diodes, and hot objects with surface temperatures greater than 500°F (260°C). Infrared films are more commonly used to photograph subjects which selectively transmit or reflect near-infrared radiation, especially in a manner different from visible radiation. Infrared photographs taken from long distances or high altitudes usually show improved clarity of detail because atmospheric scatter( haze ) is diminished with increasing wavelength and because the contrast of ground objects may be higher as a result of their different reflectances in the near-infrared. Grass and foliage appear white because chlorophyll is transparent in the near-infrared, while water is rendered black because it is an efficient absorber of infrared radiation.
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