Bolt VS-210, Руководство пользователя

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Reading the Exposure Chart
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3. By flash-to-subject distance and ISO:
A. Select the flash-to-subject distance you want to use on the top of the chart.
B. Follow its vertical line until it intersects with the diagonal line of the ISO/ASA setting you want to use.
C. Follow the horizontal line at the intersection over to the aperture setting on the right of the chart.
D. Set the f-stop indicated by the horizontal line on your camera.
Using the guide number to calculate exposure: The VS-210’s guide number is 72 feet / 22 meters at
ISO 100. You can use this to calculate the
appropriate aperture setting with this formula:
Aperture (f-stop) = guide number / flash-to-
subject distance.
For example, if your subject is 6 feet away, your
aperture should be f/12 (or the closest full stop,
f/11), since 12 = 72 / 6.
1.6 2.3 3.2 4.5 6.4 9 13 18 m
5.2 7.5 11 15 21 30 43 59 ft
25
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100
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400
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2.8
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5.6
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11
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