Advertisement
* In.manual exposure, you can shift consciously the indicator
blinking on and off or steady on to make the exposure either
under or over to take the kind of picture desired.
ffi u"a hced Instrudti6fit*
13. Depth of Field
When focusing on a certain subject, there is an area both in front
and behind the subject that can be held in focus. This range is called
the.depth of field. When the range is wide it is a deep defth of field
and when the^range is narrow it is a shallow depth of field. Depth of
field has the followins characteristics
( l)The higher the F v:alue the deeper the depth of field, the lower
the F value the shallower the depth of field.
(2)At the same F value, the shorter the focirl length of the lens. the
deeper.the depth of field. and likewise. the lonfer the fbcal length
of the lens. the shallower the depth of field.
-
(3)The farther the distance from the subject. the deeper the depth
of field and the shorter the distance from the^subiect. ihe
shallower the depth of field.
(4)From. the p-osition at which the subject is in focus, the depth of
fleld is shallower to the rear and deeper to the front.
* Fig.27 is a test photograph showing-how
depth offield works.
range set to 5 meters and F stop set to F8. When we read the ranse
graduations lwirhin rhe "8" range lhat is on both sides of the indei.y
that coffesponds to F8 at this time, the range is about 3.4 meters to
about^9.7 meters and subjects within that range will generally be in
clear focus.
1 4. I n fr a r e d p h o t o gr ap h y ( F i g . 2 9 )
An offset in lbcus in infiared photography must be compensated
for because the positions at which the subie'ct will be in fbcus under
in.frrrred light and under visible light are different.
N/ Moye the distance at which the subiect is in focus to the red line
(inl'rared line) nexr to lhe index.
If the focus results are 5 meters, for example, move the number
"5" on the lens distance scale to the infrared line index oosition.
* Infrared photography requires the use of infrared film and filters.
For more detailed information, see the instructions that
accompany infrared film.
* The 90mm/F2.8 KM rnount type M-Hexanon lens has no infiared
index because of the subject depth of field eraduations. For
more detailed information, see the instructiois that come with
the 90mm/F2.8 lens.
1 5. Exposure compensation photography
lncorrect exposure may result when you snap the shutter in taking
pictures against backlight or extreme difl'erences in brightnesi
between the main subject and the background. At those times,
compensate for exposure. There are two methods of exposure
compensation (see Figs. 30 and 3l).
1) Using the exposure compensation dial (Fig. 30)
In both focus priority AE photography and manual exposure
photography, the standard values set for exposure compensation
are shown in the finder.
V Tum exposure compensation dial @to set the index to the desired
exposure value. The exposure values can be set in stcps of one-
third each from -2EV to +2EV.
Depth of Field Checking
Therange. for depth of field can be read by the graduations for
d.epth of field that are on every lens. The figureslowed on both
sides.of the lens range/F index are the depthbf field graduations.
The depth of field graduations are written in relation-io the ranse
graduations so that the depth range can generally be read from t[e
distance graduations.
How to read depth of field graduations
tFis. 28)
Say, lbr example, we are taking pictures with a 50mm/F2 lens and
5 7
Advertisement
