Three-Dimensional Photography - Principles of Stereoscopy

MOUNTING, TRANSPOSITION AND SPACING 77

objects A, B, C and D included in the same positions. However,

instead of two eyes, we have two camera lenses LL and LR. The

rays from the objects pass through these lenses and form a dupli-

cate of the picture plane behind the lenses at fp-fp. It will be

noticed however that, due to the crossing of the rays in the camera

lens, these images are reversed in relation to the images in the

picture plane. Right and left and top and bottom are reversed.

This is familiar in ordinary camera work, and the two cameras

i“

\

f 2

~ L

Fig. 5-4.

’LR

Fig. 5-5.
which make up the stereo instrument act individually just like
any ordinary camera.
In Fig. 5-5 we have the deer as an object. In the original we
have arbitrarily designated the left and right aspects with the
letters “L” and “R.” The original is duplicated at the top of the
figure. At the left we see the visual sequence. The two eyes see
the two stereo aspects L and R, and each of these is independently
inverted upon the retina. The neuro-psychological mechanism of
stereo vision then synthesizes these aspects to form the final repro-
duction of the original.