sky, but shaded from the direct rays of the sun.
The shady side of a
building is an excellent example.
But there must be overhead skylight.
Shade under a low, densely leafed tree or an awning is not "open". Cloudy
dull and open shade need three stops more light than bright sun does.
f. The daylight exposure table helps you determine what setting to use
outdoors. Once you have decided what the subject's brightness is and what
type of lighting there is, you set the aperture to the setting where the
rows and columns intersect (Table 1-7).
4.
One final adjustment might need to be made. If the subject is fully
lit by the sun behind you, you're all set; use the exposure exactly as it
comes from the table. This is called front lighting. But if the sun is to
one side shining across the subject so that part of it is lit by the direct
rays of the sun and the rest by the light of the sky, you should open your
lens one stop from the table's recommendation so that the shadows still show
some detail; this is side lighting. If the sun is behind your subject and
shining in your face, then you should give two stops more than the table
indicates.
This is called back lighting.
Of course, if the lighting
conditions are cloudy dull or cloudy bright, the shadows are so weak you
don't have to worry about making these corrections; they are necessary only
in bright or hazy sun.
a. You don't have to memorize Table 1-7, but it would help. What you
must remember is what the subject and lighting conditions described above
mean; then, think of the "sunny f/16 rule". That is, in bright sun with an
average subject, use a basic exposure of 1/ISO at f/16.
Then make
adjustments based on the subject brightness and lighting conditions you are
actually photographing.
b. One final caution about using this table.
It only works outdoors,
and then only two hours after sunrise until two hours before sunset. Beyond
these times, the lighting conditions can vary widely and the table is almost
useless.
Learning Event 6:
DESCRIBE HOW TO USE A LIGHT METER
1.
What about the times and places where the daylight table doesn't work?
How do you find the exposure then?
For the first hundred years of
photography's existence, the answer was, "Guess". There were a lot of hints
for making a good guess, but for the most part, experience and judgement
were the only way. Today there is a much better way to find an exposure and
that's with a photoelectric light meter.
2.
Sometimes these devices are called "exposure meters," but that's a
somewhat misleading term.
The simple fact is, that no matter how
sophisticated they are, they really only measure the amount of light falling
on a light-sensitive element. The calculator translates this to a reading
of exposure. Keep in mind that this is only suggested exposure. You must
still use some judgement, but if you do you will seldom get truly bad
results using a meter.
For the word "judgement' you could substitute
"guess," but at least with a
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