User manual
speed
of
·d·,
part
of
a second has
been
proven
by
actual
test,
to
be sufficiently
high
to
arrest
motion
when
the
Aeroplane is
traveling
at
80
or
go
miles
per
hour,
at
an
elevation
of
3500
feet.
The
lens
fitted
to
the
camera
is
unalterably
set
at
a
point
that
includes all
objects
located
beyond
750
feet
within
the
area
of
definition.
The
dia-
phragm
system
of
the
lens is
conveniently
controlled
from
outside
the
instrument
by
mea"RS
of
the
dial and
pointer
D.
As a
protection
against
exposure
of
the
lens
to
fog
01'
mist,
often
resulting
in
impairment
of
the
photographic
record, a safety
shutter
is
located
in
the
front
aperture
N
of
the
camera,
directly
in
front
of
the
lens.
This
safety
shutter
is
automatically
opened
and
closed
with
the
same
action
of
the
trigger
that
releases
the
shutter.
Midway
between
the
front
and
back
ends
of
the
camera
body,
strap
rings K
are
located
to
accommo-
date
shoulder
straps,
for
supporting
the
camera,
allowing
the
operateI' ti'ee use
of
his
hands
in an
emergency
.
Shutter
Speed
Plate
X,
attached
to
each
camera,
gives
the
approximate
shutter
speeds,
in
fractional
parts
of
seconds,
obtainable
with
the
various cur-
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