Nikon D90 User Manual page 207

❚❚ Manual
Choose a flash level between Full and 1/128 (
built-in flash has a Guide Number of 18/59 (m/ft., ISO 200, 20°C/68°F).
❚❚ Repeating Flash
The flash fires repeatedly while the shutter is open, producing a
strobe-light effect. Press 4 or 2 to highlight the following
options, 1 or 3 to change.
Option
Output Choose flash output (expressed as a fraction of full power).
Choose the number of times the flash fires at the selected output. Note that
Times depending on shutter speed and the option selected for Frequency, the actual
number of flashes may be less than selected.
Frequency Choose how often the flash fires per second.
A
"Times"
The options available for Times are determined by flash
output.
1
/ of full power). At full power, the
128
Description
Output Options available for Times
1/4
1/8
1/16
1/32
1/64
1/128
2
2–5
2–10
2–10, 15
2–10, 15, 20, 25
2–10, 15, 20, 25, 30, 35
L
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