Canon Speedlite 550EX Instructions Manual page 60

60
[2] Wireless E-TTL Autoflash
Wireless E-TTL autoflash with multiple Speedlile 550EXs can be used in one
of two ways:
(1 1 _ 0FF
(21 _ 0N
All slave units fire at the same flash output.
Slave units wilh ditlerent slave IDs (A, B, or C) can be
fired at different flash outputs to produce a flash ralio,
A flash ratio can be sel only with the EOg -S.
With Ihe EOS Elan II·IIE/SO·SOE. EOS Rebel GiSOON. EOS IX, and EOS IX LiteflX7. a nash ratio
caonol be set with the maSler unit.
1. Wireless E-TTL Autoflash With Flash Ratio OFF
If no flash ratio is desired, the slave 10 does not matter. It can
be
A, B, or C.
All the slave units will fire al the same flash output. The E-TTL autoflash
system controls the lolal flash amount automatically to obtain a correct flash
exposure .
• Master Flash ON + Slave Unit(s)
For indoors
.----T~ lO"m ::: f
32.8 ft
12m 139.4ft
For outdoors
80"
Bm126.2ft
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