Canon SPEEDLITE 580EXII Mode D'emploi page 36

Multi-Speedlite, Wireless Lighting Configurations
You can create two or three slave groups and set the flash ratio for E-
TTL II autoflash shooting (p.41 - 45).
Wireless flash with two slave groups
(p.41)
Indoors
15m
A
(49.2ft.)
Outdoors
10m
B
(32.8ft.)
o
80
8m (26.2ft.) 12m (39.4ft.)
Wireless flash with three slave groups
(p.43)
Indoors
C
15m
A
(49.2ft.)
Outdoors
10m
B
(32.8ft.)
o
80
8m (26.2ft.) 12m (39.4ft.)
35