Stereo slide viewer Slide viewer

a view-master model e of 1950s

the practice of viewing stereoscopic film-based transparencies through small magnifying viewer dates @ least 1931, when tru-vue began market black-and-white 35 mm filmstrips fed through handheld viewer made of bakelite.

in 1939, radically different viewer, designed use commercially prepared stereo images, introduced view-master. images in color on small pieces of kodachrome film came mounted in rectangular openings near edge of cardboard disk, which, despite being quite flat, officially known view-master reel . each reel contained 7 image pairs, left-eye , right-eye images being diametrically opposite. lever used rotate reel in increments present each image pair in sequence. eventually, viewers available in several models, including illuminated flashlight bulbs powered line current transformer or batteries, talking view-masters. viewers , reels in view-master format still being made today. 1 category of material still in production children s fairy tale story scenes , brief stories using popular cartoon characters. these use photographs of three-dimensional model sets , characters. category scenic views associated tourist destination, typically sold @ gift shops located @ attraction.

a major innovation in 1947 introduction of stereo realist camera , viewer system. using kodachrome or other 35 mm slide film, equipment made startlingly lifelike amateur stereoscopic color photography possible @ reasonable cost. system well-advertised , experienced surge in popularity. other makes of cameras employing realist format began appearing in 1950s. stereo realist , competing products can still found in estate sales , elsewhere, , enthusiasts still use them take pictures.

an advantage offered transparency viewing compared earlier card stereoscopes wider field of view may presented because images, being illuminated rear, may placed closer lenses. in ordinary viewers, simple, inexpensive lenses have relatively long focal lengths entirety of images appear reasonably sharp, , consequently field of view occupied images small. magnify images occupy larger visual angle , still sharp , undistorted, suitable high-quality multi-element short focal length lenses must used. such lenses quite expensive , not found in stereo viewers. optimum realism, images viewed must created using equivalent wide-angle camera lenses.