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MORE  ABOUT  THE  PRISMATIC  VIEWER

The viewer simulates a "cross-eyed view" of two pictures, overlapping them.  This means that you could see the 3-D effect even without the viewer.  However, most people find it difficult to cross their eyes and focus at the same time.  The two prisms take care of the "crossing" part.  (By the way: it doesn't matter which side of the viewer is towards you). 
    Classic stereo viewers use a pair of prisms to overlap two pictures.  Normally the prisms are curved, acting as lenses.  Such lenses work only with particular image sizes.  The antique Stereoscope had its own kind of postcards, each 3-D slide viewer uses a certain kind of film format, and so on. Your viewer has only two basic prisms - without any lens components.  Since your eyes are doing the focusing, you are free to move away from the two pictures.  This allows you to see stereo pairs of ANY size, on ANY medium - computer monitor, FAX paper, photo album, etc.  The trade-off is that you must spend a second to find the right viewing distance.
After you see the first 3-D picture, it becomes very easy to view all of them.  Also, you can show other people how to use the viewer - it's much easier than to have them read this "How-to".  

More hints:  Keep the viewer close to your eyes when you move to find the distance.  Also, the first image in our Showcase (the locomotive) has a red circle with a "1" painted on it.   When the two circles from the left/right views overlap in the middle image, this image becomes 3-Dimensional.  

REMEMBER to always look at the picture STRAIGHT ON, not from a side or from above.  For example, if you view a 3-D pair printed on paper, hold it  perpendicular  to your line of sight.  Also,  DO  NOT  TILT  THE  VIEWER  (or tilt it just slightly to compensate for a not-so-perfect position).  After you view a few pictures with the viewer and get used to it, learn how to cover the side images.  The best way is by moving your fingers toward the center.  For wide pictures, you can also move the viewer a bit further from your eyes, until the edges of the prisms cover most of the side areas.  Keep your distance from the screen while doing that. 

If the viewer gets dirty, wipe it with a soft, semi-moist cloth.  For more information please see the User Agreement. 

IMPORTANT:  If you or someone who tries the viewer for the first time can't see the 3-D effect in 2-3 minutes, do not insist.  A small percentage of people cannot see stereo images, regardless of what display method is used.  There's no reason to make somebody feel bad about it.  If you happen to have this problem, please feel free to send your viewer back for a full refund, within 30 days of delivery date.