Polaroid SONAR OneStep SX-70, Руководство пользователя

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How sonar focusing works
As you beg in 10 press the shutter
button, your camera releases sound
waves
to the central part of the scene
(approximate area marked in blue).
The frequencies are far beyond our
range of hearing and
travel
at the
speed of sou nd (1 ,100 feet per
second).
3
The split second it takes for the
sound to reach your subject and
the echo to return is fed into a tiny
electronic computer inside the
camera.
The computer uses this time mea-
surement to calculate
the distance
between the camera lens and your
subject, th en signais a motor to turn
the lens until your subject is in
sharp focus.
This extraordinary chain of events
takes place in less than
113
of a
second.
((
((
. .. echo returns to camera.
-- Total Time
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