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Depth of Field
When a
lens
is focused on
a
given subject,
objects
in t
he
foregrou nd
and
background wi
ll
appear acceptab ly
sha rp
in
the picture.
The
extent
to
w
hi ch all
objects w
ill
be
reproduced acceptably
sharp in
the picture is ca
ll
ed
t
he
depth of
fie
ld.
In
the photo
taken
at f/
1,4,
the
foreg rou nd and back-
ground objects appear blurred.
Th
e
depth-of-field sca le on
the
lens
barre
l
w
ill
show
th
e
extent of
the
depth of
f
ield
at different aperture settings.
I
n
case
the standard 50 mm lens is stopped
down t
o f
/
16
and focused
at 2 meters
,
th is
sca
le
wi
ll
ind
ica
t
e
tha
t
all
objects
w
ithin the
range of
about .1.5 and
3
meters
wi
ll
appear acceptably
sha
rp
in the
picture
.
•
With
a
specific lens, the depth of f ield var ies
accord-
ing to the fol
low
ing;
~
It increases as
you
stop
down
the lens.
[f]
It is
more extens ive
in the backg
round
t
han in
t
he
foregrou nd.
[J]
It is
more extens ive as you
focus
on a
d
ista
nt subject
.
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