Main Switch; High-Speed Sync (Fp Flash) Switch - Canon Speedlite 420EX Instruction Manual

Main Switch

The main switch has the following settings.

High-Speed Sync (FP Flash) Switch

The high-speed sync switch has the following settings.
• When the 420EX is used with a Type-A camera and the switch is set to <
setting a shutter speed faster than the camera's fastest sync speed sets the
high-speed sync mode. And using a shutter speed slower than the fastest sync
speed sets the normal sync mode.
• When a Type-B camera is used, the normal sync mode takes effect regardless
of this switch's setting.
14
Turns off the power.
Turns on the power.
After 90 sec. of non-use, the SE
(Save Energy) mode takes effect
automatically to turn off the 420EX
and save battery power.
• To cancel the SE mode, press the
test firing button.
Sets the normal sync mode.
Sets the high-speed sync mode.
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