Nikon 4807 - SB 900 Speedlight, Руководство пользователя

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Flash modes and functions
Taking close-up photographs with bounce-down flash
A
B
ISO sensitivity 100 200 400 800 1600 3200 6400
Factor (m/ft) 2/6.6 2.8/9.2 4/13 5.6/18 8/26.2 11/36 16/52.5
t
When shooting subjects closer than 0.6 m (2 ft.)
With the SB-900 attached to the camera, sufficient illumination of the subject
cannot be obtained.
In this case, use the SB-900 off-camera by attaching the optional TTL Remote
Cord as shown below.
When monitor pre-flashes are fired, distance information from the lens is used
to determine the correct exposure. In this case, position the camera (A) and the
SB-900 (B) at equal distances from the subject. •
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t
Setting the aperture in off-camera close-up fl ash operation
Calculate the aperture by using this equation and table.
To ensure the correct exposure, use an aperture smaller (larger f-number) than
the one obtained from the equation.
f/stop
≥
Factor ÷ Flash-to-subject distance
For example, at an ISO sensitivity of 100 with a subject 0.5 m (1.6 ft.) away and
the wide-flash adapter in place, the suggested aperture is:
f/stop
≥
2 ÷ 0.5 = 4 (in meters)
f/stop ≥ 6.6 ÷ 1.6 = approx. 4 (in feet)
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Notes on using a wideangle lens
Generally, when using a wideangle lens, the distance between the
camera and subject differs from the center of the frame to the periphery,
so the peripheral area might not be sufficiently lit in some cases. •
Use TTL Remote Code SC-29, SC-28 or SC-17.