Minolta XE-1 - Holding the Camera Correctly

20
EXPOSURE.CONTROL
FUNDAMENTALS
The two
camera exposure-control
settings
are lens opening
(aperture)
and shutter
speed.
The size
of the
aperture
determines the
amount
or volume of light
reaching
the film
from
a
given
subject
and lighting.
The shutter
speed
determines
the length
of time
this light
acts
upon
the film.
Apertures
are
expressed
in
f-numbers,
which
are
larger
for
small openings
and
vice
versa
(e.g.,
f/16
represents
a
small
opening, f
12
a large
one)
. Shutter speeds
are
expressed
in seconds
or
f ractions
thereof,
which
are
generally
the reciprocals
of the numbers
shown
shutter-speed
scales.
(e.g.,
60
=
1l60
sec.,
but
2s
-
2
f ull seconds).
At usual
apertures, each f-number
setting
(e.9.,
f/8)
lets
in twice
as much light
as
the
next numerically
larger
one
$l1"ll
and
half as much
as the next
smaller
(f/5.6).
Similarly,
each shutter
speed
(e.g.,
1/60
sec.)
allows light to
strike the
film
twice
as long
as the next
higher speed
(11125t.
and half
as long
as the next
lower one
(1/30).
The interval
between two standard
f-numbers
lsay,
t14
and f/5.6 or shutter
speeds
(say,
1/15
and
1
/30)
is one
"stop."
Total exposure
on
the
film is
determined
by the
combination
of
aperture
and speed.
Other things
being equal,
using the next
smaller
f
-number
(i.e.,
giving
one
stop
more exposure) will balance using
the
next
higher
shutter
speed
(i.e.,
giving
one stop less
exposure)
,
and so
on.
A
great
range
of
combina-
tions
(e.9.,
f/5.6
at 113O.
f
l4
ar
1160, tl2.B
at
11125, f
12
at
11250,
etc.) will thus
yield
the
same
total
exposure.
The specific
combination
you
choose
under
given
lighting
conditions
will
depend
upon the degree
to which
you
want
the
greater
depth
of field
(see
p.
34) of
smaller
apertures and the
greater
movement-blur
pre-
venting ability
of
faster
speeds
(p.
29).