SHUTTER SPEED DIAL
The F4 features an electromagnetically controlled vertical-travel
focal plane shutter which consists of four front and four rear
curtains.
For Manual and Shutter-Priority Auto Exposure, you can set
any of 16 different shutter speeds from 4 sec. to 1/8000 sec.
Intermediate shutter speeds cannot be set. Three other settings
- В, Т and X — are also possible. For P modes and A mode,
the shutter operates steplessly from 30 sec. to 1/8000 sec.
В Setting
At the "Bulb" setting, the shutter remains open as long as the
shutter release button remains depressed. This setting should
be used only in the Manual Exposure mode. Set shutter speed
dial to B.