Sync Speed - Canon EOS 5D Mark III Instruction Manual

Using Non-EX-series Canon Speedlites
With an EZ/E/EG/ML/TL-series Speedlite set to A-TTL or TTL
autoflash mode, the flash can be fired at full output only.
Set the camera's shooting mode to <a> (manual exposure) or
<f> (aperture-priority AE) and adjust the aperture setting before
shooting.
When using a Speedlite that has manual flash mode, shoot in the
manual flash mode.
Using Non-Canon Flash Units

Sync Speed

The camera can synchronize with non-Canon compact flash units at
1/200 sec. and slower speeds. With large studio flash units, since the
flash duration is longer than compact flash units, set the sync speed
within 1/60 sec. to 1/30 sec. Be sure to test the flash synchronization
before shooting.
PC Terminal
Cautions for Live View shooting
If you use a non-Canon flash unit with Live View shooting, set [z4:
Silent LV shoot.] to [Disable] (p.206). The flash will not fire if it is set to
[Mode 1] or [Mode 2].
The camera's PC terminal can be
used with flash units having a sync
cord. The PC terminal is threaded to
prevent inadvertent disconnection.
The camera's PC terminal has no
polarity. You can connect any sync
cord regardless of its polarity.
D Flash Photography
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