Table of Contents
Advertisement
36
Depth of field
The distance behind and in front of the
focused distance with in wh ich the image ap-
pears acceptably sharp is called the depth of
field.
It extends a greater distance behind the
focused distance than in front and is
deter-
mined by three factors
:
the aperture size, the
distance at which the lens is focused, and the
focal length of the lens in
use.
Depth of field
~~~l!14~~
0
4~~!!!1~~ 0
o
r-
Dista~ce de mise
-+I
au POint
increases as the lens is stopped down (e.g., f/2
to f/16) and becomes greater the farther from
the camera the lens is focused. I t decreases as
the lens is opened up (e.g. f/16 to f/2) and the
closer to the camera the lens is focused. Depth
of field is greater for short focal length lenses
than for telephoto's at the same focused dis-
tance and aperture.
It
is at its least for any
given lens in normal mounting when the lens is
at maximum aperture (as when metering and
focusing
normally
with
Minolta
MD-
or
Me-type lenses) and at minimum focusing
distance.
Depth-of-field preview
Depth of field at any aperture and focusing
distance can be previewed visually by push ing
the stop-down button all the way in. Th is will
stop the diaphragm down to the aperture
corresponding to the f-number preset on the
aperture ring, allowing you to see through the
viewfinder how much of the subject is
accepta-
bly sharp.
Advertisement
Table of Contents
