Infrared photography is of interest to the amateur and commercial photographer and to scientists and technologists because it produces images that are not possible with conventional photographic films. In its practice there is not much difference between infrared and normal photography. The same cameras and light sources can usually be used, together with the same processing solutions. Infrared photography, however, is usually only attempted by skilled photographers, scientists, and technicians with a particular purpose in mind.
The peculiarities of infrared photography lie in the ability of the film to record what the eye cannot see (permitting, for instance, photography in the dark); in the fact that many materials reflect and transmit infrared radiation in a different manner than visible radiation (light); in the ability of infrared radiation to penetrate certain kinds of haze in the air so that photographs can be taken of distant objects that cannot be seen or photographed on normal films; and in the ability to photograph hot objects by the long-wavelength radiation that they emit. These properties permit infrared photography to be used as an important adjunct to photography by normal light.