Canon SPEEDLITE 580EX II Instruction Manual page 42

Flash Ratio with E-TTL II
With one master unit and one slave unit or two slave groups, you can
set the flash ratio for E-TTL II autoflash shooting.
The example below has two slave units and the master unit disabled
from firing.
12m (39.4ft.)
Indoors
1Om 1(32. 8ft. )
I
I
Setting the Slave Units
Two slave units can be assigned to different slave groups by setting the
slave 10.
SLAVE
Set the wireless mode to
<
>.
(p.36)
Press the
<ZOOM/~>
button
so that <
A
> blinks.
~Kl
IHIII ,
I ,
"Z.~
I
1 .il·"'__ A _
'T'-
ETTL mlZoom 2Ymm
41