THREE INVENTIONS HAVE LITERALLY changed the way we see the world. The telescope allowed us to gaze into the heavens; the microscope, to peer into our very cells. And the camera stopped time in its tracks, giving permanency to the ephemeral and the evanescent. Those captured images stirred scientific

revolutions. "Suddenly we were able to see things we had never seen before," says curator Therese Mulligan of the George Eastman House International Museum of Photography and Film. The first images of lightning were taken in the 1880s and were the basis for naming the different types of crackling energy strikes "Doctors and physiologists used photography to examine diseases. Photographing the insane was the beginning of modern psychology," she adds.

The Eastman House (www.eastman.org) is a fitting homage to the man who revolutionized photography. The founder of Eastman Kodak, George Eastman simplified the elemental tools for taking pictures: cameras and film. In 1880, he invented a gelatin dry-plate coating that soon replaced clumsy wet-plate glass negatives. In 1900, he introduced the Kodak Brownie camera, which clicked with the American public at the low price of one dollar (film cost just 15 cents a roll). His chemists developed flexible celluloid film for one of Thomas Edison's new moving-picture cameras and helped spur the growth of the motion picture industry. And it was Eastman who set the international standard for moving film at 35 mm, four perforations per frame.

The museum, housed at Eastman's estate in the heart of Rochester, New York, is a mecca for photography and film buffs. Built in 1905 with the latest modern conveniences, including a central vacuum system, an internal telephone exchange, and an elevator, the 50-room mansion now contains a staggering 400,000 prints and negatives, 25,000 films, and 45,000 books. Its technology collection holds more than 23,000 items, including early daguerreotype cameras and some unusual Eastman Kodak products, including Coquette cameras with matching compacts and lipsticks and snakeskin- and alligator-covered Kodaks from the 1930s.

To learn about the history of photography, visitors should start with the Pencil of Nature interactive exhibition. Although photography grew directly from scientific investigations of the 1700s into chemistry, light, color, and vision, to the public it smacked of magic and alchemy and early on was often called "the black art." The dark chemical stains left on photographers' hands also contributed to the name.

Gallery exhibitions feature classic and contemporary photography, such as Dorothea Lange's 1936 portrait of a California migrant woman and Eddie Addams's 1968 photo of a Vietnamese general executing a countryman point-blank in the head on a Saigon street. Visitors can also call ahead to make an appointment to see major photographic documents of the Civil War or to screen films from the private libraries of Cecil B. DeMille, Martin Scorsese, and Spike Lee as well as to view unique cameras and other equipment usually kept in protective vaults. Whether your interest in photography is general or very specific, a trip to Eastman House will tutor your eye and enrich your soul.