Depth-of-field scale
The distance behind and in front of the
focused distance with in which the image ap-
pears acceptably sharp is called the depth of
field. Besides being greater the shorter the focal
length of the lens and vice versa, this increases
as the lens is stopped down and becomes
greater the farther from the camera the lens is
focused. It is at its least for any given lens in
normal mounting when the lens is at maximum
aperture (as when metering and focusing nor-
mally with Minolta MC lenses) and at minimum
focusing distance.
Focused distance
The near and far limits of acceptable sharp-
ness can be determined from the depth-of-field
scale on the lens barrel. With the lens focused at
a given
point, the
image will be in satisfactory
focus from the nearer value to the farther value
on the distance scale indicated by the depth-of-
field scale marks for the aperture to be used.
For example, if a 50mm lens is focused at
5m (about 16 ft.) and the aperture is f/8, the
appropriate graduations to left and right of the
index on the depth-of-field scale indicate ac-
ceptable sharpness from about 3.4m to 9. 7m
(approx. 11 to 32 ft.).
5 7 HI 15 30
00
1.5 2 3 5 10
I I I I .t. I I I I
16 8 4• R8 16
•
-r~ --- - ----~ --------
1.422.8 4 5.6 8 11 16
'11
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