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DEPTH OF FI ELD
When the
camera
lens is focused
on a
given
subject, objects
in
the
foreground
and
background
wi
Il
appear acceptab
ly
sharp
in the
picture. The
area
in
which
objects
appear
sharp ly
defined is
ca
ll
ed
the depth
o
f
field.
Photos
on this page were
taken by maintaining the same
focus (Iens focused
on
the median
object).
At maximum
apert ure
(f/2.8), the objects in the foreground and
ba
ck-
ground 2IPpear blurred. When the
lens is
stopped
down
to
f
/
16, however, the same
foregrou
nd
and backaround
objects
will
appear sharply
defined.
In
ot
her
words, the
depth
of
field becomes
more extensive as
you stop down
the
lens .
•
The depth
of
field for a given
lens
aperture
ca
n
be read
off
the depth-of-field
sca le on the
lens barrel.
45
When the
lens
is focused
on
a
subject at a
distance of 2
meters,
for
examp
le,
the depth-of-field scale wi ll show
that
the extent of
the depth
of
field will be from about
1.4
to 4 meters when
th
e
lens is
stopped
down
to
f/16.
I
n
other words, the extent enclosed by the figure 16
(or
the figure
equiva lent
to the aperture
setting
in
use) on
both
sides of
the
red
index w
ill
be the area
in
which
ali
objects wil
l
appear
acceptably sha
rp
in the picture
(depth
of fie
ld)
!2
F 2.8
F
16
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