Nikon F4 - Rear-Curtain Sync Flash Photography

Rear-Curtain Sync Flash Photography
When using the Nikon SB-24, you can synchronize the flash to
the instant just before the rear (second) curtain starts moving.
Set the SB-24's flash sync mode selector to "
REAR. " This lets
you turn available light into a stream of light that follows the
flash illuminated subject. Rear-curtain sync flash photography
is especially effective at slower shutter speeds.
In PH , P or A mode, shutter will operate as slowly as 30
seconds, depending on the background brightness.
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Front-curtain sync