Nikon Nikkormar FT3 - Infrared Photography; Silver-Oxide Battery

INFRARED PHOTOGRAPHY
----
In infrared photography, the plane of sharpest focus
is slightly more distant than the one produced by
visible light and seen by the naked eye through the
viewfinder. To compensate for the shift in focus,
Nikkor lenses have a red dot or line on the lens barrel
near the color-coded depth-of-field index scale on
top of the lens. After focusing the image sharply
through the viewfinder, turn the focusing ring to the
left until the red dot lines up with the prefocused
distance.
For example, in the picture below the SOmm f/1.4
lens has been focused at infinity (00). The focusing
ring
is turned slightly to the left so that the infinity
mark appears in line with the red dot. When lenses
having a focal length
of SOmm or less are stopped
down to f/8 or smaller, no adjustment is necessary:
at such small apertures and short focal lengths, lenses
have
enough depth of field to compensate for the
shift in focus.
SilVER-OXIDE BATTERY
The Nikkormat FT3's meter circuit is powered by a
single 1.S-volt silver-oxide
battery located in the
battery chamber on the camera baseplate. When the
battery is exhausted, the meter will cease to function
all at once. To replace the battery, unscrew the cap
over the
battery chamber with a coin or similar object.
When installing a new
battery make sure that the plus
(+) side faces out.
Note: If the meter is exposed to bright light at below·freezing
temperatures over a long period of time, it may malfunction
or cease to operate until the tempe : rature rises again. There·
fore, be careful not to leave the meter on for more than
three minutes at a time in cold weather.
Caution: Never throw discarded batteries into a fire.
25