Canon SPEEDLITE EL-10 Advanced User's Manual page 81

Autoflash with groups of receivers (
E-TTL II / E-TTL autoflash photography is possible with two or three receiver groups,
and the flash ratio (proportion of flash output) can be adjusted as needed.
(1) 2 groups (A, B)
(2) 3 groups (A, B, C)
Caution
Take a few test shots in advance, and test flash firing (
Transmission range may be shorter depending on factors such as Speedlite
positioning, the surrounding environment, and weather conditions.
Note
Set up receivers using the included mini stand.
, )
81
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