Nikon FM, Инструкция по эксплуатации

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EXPOSURE MEASUREMENT
The Nikon FM’s built-in exposure meter utilizes Nikon’s
proven center-weighted through-the-lens metering system
which is cross-coupled with both the shutter speed control of
the camera and the aperture control of the lens mounted on
the camera. The meter reads the intensity of the light coming
through the lens over the entire focusing screen at full aper-
ture but favors the central 12mm-diameter area outlined on
the screen— allowing you to make precise readings and mak-
ing for overall balanced exposures. Determining Degree of Exposure
The viewfinder has three exposure indicators visible within
the viewfield: + for overexposure, o for correct exposure and
— for underexposure. These indicators have corresponding
LED’s which light up when the film advance lever is moved
to its 30
°
stand-off position; as you can see in the chart on the
left, there are five combinations possible. Also included in-
side the viewfinder as aids to exposure determination are the
shutter speed selected and the lens aperture setting. With non-
AI type lenses, the lens aperture is not visible. To determine
correct exposure, first switch the meter on by moving the film
advance lever to its stand-off position. One or two of the
LED’swill light up opposite the corresponding exposure indi-
cator/s to show you the precise degree of exposure. If the +
indicator LED lights up, increase the shutter speed or decrease
the aperture—or vice versa— until the o indicator LED lights
up and the + indicator LED turns off; the procedure is the
same if the—indicator LED lights up alone or with the Vindi-
cator LED.
It is normally impossible for all three LED’s to light up at the
same time, or for the + indicator LED and—indicator LED to
light up simultaneously. The exception to this is when photo-
graphing a television screen. The rapidly scanning spot pat-
tern that produces the TV picture results in a cyclic effect that
causes all three LED’s to light up when the exposure setting is
correct.