<?xml version="1.0" encoding="utf-8"?><mads xmlns="http://www.loc.gov/mads/" xmlns:mods="http://www.loc.gov/mods/v3" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.loc.gov/mads/
mads.xsd"><authority><topic authority="http://AATesaurus.cultura.gencat.cat/aat/getty_en">stereoscopic photography</topic></authority><related type="other"><topic>stereoscopy</topic></related><related type="other"><topic>stereoscopic photographs</topic></related><related type="other"><topic>stereoscopic cameras</topic></related><related type="broader"><topic>picture-taking techniques</topic></related><variant type="other"><topic>photography, stereoscopic</topic></variant><variant type="other"><topic>stereography</topic></variant><variant type="other"><topic>stereophotography</topic></variant> <note xml:lang="en"><![CDATA[ Refers to techniques used to produce the appearance of three-dimensionality in photographs by using two images made at slightly different positions, mounting them side by side, and viewing the pair through a stereoscope or other device. This type of photography was extremely popular in the Victorian period. The process was described in 1832, but the techniques were perfected only after 1856, when a twin-lens camera was designed to take two pictures of the same scene simultaneously. The viewpoints of the photographs were 2 1/2 inches apart, which is approximately the normal distance between human eyes. ]]></note></mads>