A 35mm panoramic stereoview format designed and introduced in Japan at the 1970 Osaka Expo. The Pan-Pet viewer was manufactured by Japanese company, Gakken Co.Ltd.
The Pan Pet offered true panoramic 3D photos that were so wide that the winding knobs were kept busy as you rolled the film back and forth to "pan and scan" the entire 3-D image. The "window" itself gave a 4:1 panoramic crop of the sometimes wider images (and sometimes shorter ones) rolling behind it. Using 35mm film, each cartridge has 20 panoramic stereo pairs. The pictures are reflected into the lenses by two offset mirrors, set at 45 degrees. The translucent white cover permitted light to come in.
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