The stereoscope provided 19th-century viewers with the illusion of 3D depth, in much the same way as the virtual reality headsets of today. In the pre-television, pre-movie days, families would gather round the stereoscope instead.
Stereoscopic photography uses the binocularity of human vision to recreate the illusion of depth. Our eyes are set slightly apart, meaning each eye sees the world from a different angle. Our brains combine these two images into one, giving us spatial depth.
The stereoscope allowed viewers to see a pair of two-dimensional images taken from slight different angles – one for the right eye, one for the left. Viewed through a stereoscope, the brain combines the two offset photographs into one, giving the impression of a 3D image.
Wiggle stereoscopy is a technique which combines the two stereographic images into one animated GIF. The New York Public Library’s Labs project developed Stereogranimator a few years back to allow users to create their own – although we’ve slowed ours down a touch.
The two near-identical prints were made with a double-lens camera. They originally came pasted on a card, as shown above.
“Between the 1850s and the 1910s, stereographic images were a mainstay of home entertainment, perhaps second only to reading as a personal leisure activity,” says the NYPL. “Like television, stereos were an intimate medium viewed by individuals or small groups at home, or at churches, schools or clubs”
Photographers around the world produced millions of stereoscopic views between 1850 and 1930.
Quality ranged from sharp original silver prints to cheaply produced copies, and eventually half-tone photomechanical processes.
Stereoscopes varied from small handheld devices for viewing single images to large pieces of furniture that could display a changing series of 50 or more views.
“The makers of stereos were equally diverse,” says the NYPL. “Into the 1880s, they ranged from eager amateurs photographing family scenes for private distribution to the famed camera artists of the day who demanded high-quality publishing and distribution and got it. By the 1890s, stereo photographers tended to be skilled and enterprising professionals who either sold their images to large commercial producers or worked anonymously under contract to them.”
The rise of movie newsreels and illustrated magazines like Life spelled the end for stereoscopy in the 1930s.
Tens of thousands of stereographic images are available on the NYPL Digital Collections website.
There are instructions on how to make your own simple stereoscope here.
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