photography of objects under a microscope. Such opaque objects as metal and stone may be ground smooth, etched chemically to show their structure, and photographed by reflected light with a metallurgical microscope.

Biological materials may be killed, dyed so that their structure can be seen, and mounted on glass slides for photographing by transmitted light using ordinary light microscopes; or, by using ultraviolet, infrared, electron, or X-ray microscopes, sharp photographs can be made of living, unstained specimens. Cinephotomicrography, taking motion pictures of magnified objects, is useful in studying organism growth, colloidal movement, and chemical reactions.