Olympus OM-3Ti, Инструкция по эксплуатации

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THE FASCINATING RESULTS OF CREATIVE EXPOSURE AND
HIGH-SPEED SYNCHRONIZATION By Aklo Kojima
Have you always been satisfied with the resulting images
when using the camera's meter or an automatic exposure
system?
Chances are, most of the time you've been happy with
the results. Occasionally, however, you may have been
disappointed by photographs that didn't turn out as
expected, especially shots with backlighting or other
special lighting conditions, or those shots where you tried
to capture a particular mood or express your own
creativity.
Color reversal films, in particular, allow for only a narrow
latitude of exposure so that in many cases satisfactory
results are not obtained with simple automatic exposure.
Generally speaking, the results given by a camera's light
meter represent exposure values obtained by a metering
system that has been specifically adopted for that
camera. They do not always represent data as the result
of analytical measurement of various conditions such as
the subject's brightness range and distribution as well as
contrast. In actual shooting conditions, however, there is
often a very wide brightness range (luminance range) —
from the brightest spot to the darkest spot in a picture. In
some landscapes, for example, there can be a difference
of as much as 8 exposure values (EV) in the brightness
range of an image, representing a brightness/darkness
ratio of more than 1 : 200. The subject brightness range
that a film can reproduce (or an effective exposure range
of a film ) is limited to about 4 - 5 EV. Therefore, in many
cases it is impossible to accurately reproduce the subject
in its entire range on film.
The automatic exposure system (AE) on ordinary
cameras generally selects exposure using an exposure
meter in combination with the film speed. However, if
photography is to be a means of communication, the
photographer must control the tone of the picture in order
to most effectively emphasize the mood and expression
of the subject. To do this, it is necessary to choose the
exact spot on which you want to emphasize the desired
tone and match this spot to the effective exposure range
of a film.
To meet such exposure requirements, the following three
types of exposure are available.
Center-based exposure is the most commonly used type
of exposure. By matching the center of the subject's
brightness range to the center of the film's exposure
range, the subject is reproduced with greater emphasis
on the center-measured tone. If the brightness range is
greater than the range of the film, the extremes will be
ignored.
Shadow-based exposure gives the highest priority to the
shadow area in the subject brightness range. The tone in
the highlight area that is not covered may be ignored.
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