Care of Binoculars
Binoculars are fairly delicate instruments; they
cannot stand much knocking about. Therefore, keep
them on a short strap when wearing them to prevent their
banging against solid objects. Always keep the strap
around your neck. Never hold binoculars over the side of
the ship without the strap being around your neck. Many
pairs of binoculars have been lost over the side in this
manner. Keep the lenses dry; otherwise, you will not be
able to see properly. Don’t let them become overheated;
the cement around the lenses might melt. Above all, keep
them clean. You must be careful, however, not to damage
the lenses when cleaning them. First, blow off loose dust;
then breathe on the lenses (except in freezing weather)
and gently clean them with lens paper. Rags, plain paper,
handkerchiefs, or your sleeve or shirttail should not be
used, as they might scratch the lens. You can usually get a
supply of lens paper from the QMOW.
NIGHT VISION
Have you ever walked from a lighted theater lobby
into the darkened theater? You would almost be blind
for a few minutes. As your eyes become accustomed to
the weak light, your vision gradually improves. The
same situation exists when you go on night watch
directly from a lighted compartment. After 10 minutes,
you can see fairly well. After 30 minutes, you reach
your best night vision. This improvement of vision in
dim light is called dark adaptation.
Specially designed red goggles are provided for you
to use before you go on night lookout duty. These goggles
prepare your eyes for darkness without affecting your
ability to play games, write letters, or read before going
on watch. You should wear them without interruption for
at least half an hour before going on watch. Even then, it
will still take you at least 5 minutes more in darkness to
develop your best night vision.
After your eyes are dark adapted, you must learn to
use your night eyes. In the daytime, you should look
directly at an object to see it best. In the dark, you need
to look above, below, or to one side of an object to see it.
This is called off-center vision. At night, it’s also easier
to locate a moving object than one standing still.
Because most objects on or in the water have a relatively
slow speed, we move our eyes instead, and the effect is
nearly as good. Therefore, while scanning at night,
lookouts move their eyes in slow sweeps across the area
instead of stopping the eyes to search a section at a time.
Your ship may be equipped with night vision
equipment. Before standing watch, be sure you are
trained in operating the night vision equipment assigned
to your ship.
SCANNING PROCEDURES
A well-trained lookout will see much more than a
“green” hand would see. In good weather, lookouts can
easily spot planes with the naked eye at 15 miles. With
binoculars and in unusually clear weather, lookouts
have detected planes at 50 miles. At night, skilled
lookouts will detect objects that the untrained lookout
would never suspect were there.
The lookout’s technique of eye search is called
scanning, which is a step-by-step method of looking. It
is the only efficient and sure way of doing the job.
Scanning does not come naturally. You must learn to
scan through practice. In the daytime, your eyes must
stop on an object to see it. Try moving your eyes around
the room or across the water rapidly. Note that as long as
your eyes are in motion, you see almost nothing. Allow
your eyes to move in short steps from object to object.
Now you can really see what is there.
Figure 3-8 shows how you should search along the
horizon. (You also must cover the surface between your
ship and the horizon.) Search your sector in 5° steps,
pausing between steps for approximately 5 seconds to
scan the field of view. At the end of your sector, lower
the glasses and rest your eyes for a few seconds; then
search back across the sector with the naked eye.
Lookouts also search from the horizon to the zenith
(overhead), using binoculars only to identify a contact.
Move your eyes in quick steps (about 5°) across your
3-17
Student Notes:
Figure 3-8.—Scanning using the step-by-step method.
