Single plate D Stereograph Oval Unidentified Estimated Dates - mid 1850s

Stereo daguerreotypes present a three dimensional image when viewed through a stereoscope. Most commonly, the two images were separately exposed. Some images were produced on a single plate, using "binocular cameras". A binocular camera has two lenses. This provides two separate pictures 2.5 inches apart, about the distance between the eyes. Although the pictures may appear the same, they are slightly different. When looked at in a viewer, which has prismatic lenses, the two views blend into one and the brain perceives this image in three dimensions the same as normal vision.