Pentax Optio 450 Operating Manual page 68

b Viewing 3D pictures by the parallel method and cross method
As our eyes are positioned about 6 – 7 cm apart, there is a very slight
deviation between what we see with our right eye and what we see
with our left eye. The difference is processed by our brain to produce a
three-dimensional image. This principle is applied to taking and
viewing 3D pictures.
3D pictures can be viewed by the parallel method where the left and
right lines of vision are virtually parallel, as when looking at a distant
scene, or the cross method where the left and right lines of vision are
crossed, as when you cross your eyes. A certain amount of practice
may be necessary to view 3D pictures without using the viewer.
b How to Assemble the 3D Image Viewer
Assemble the 3D image viewer supplied with the camera as shown
below.
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