Film Plane Indicator
This
mark,
engraved on top of the camera
body,
indicates the exact position of the film
plane.
It is
useful for measuring the exact shooting distance
from film to subject in close-up
photography.
Distances on the lens' distance scale are cali-
brated from this
mark.
It is not used in general
photography.
Note
The aperture
ring
of an
FD lens must be removed
from
" A"
before you
mount the lens on
any
of
these close-up accessories except for FD-U
Extension Tubes
and
Extenders FD
2x
and FD
1.4x,
which are designed for normal full-aperture
metering
.
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