Canon Speedlite EL-100 User Manual page 50

Wireless Multiple-Flash Photography with Flash Ratio
Setting up receivers
Autoflash with Three Receiver Groups
C
A
50
2
Set the flash group.
Set the Mode dial of each receiver to
z
the group in which it will fire (< 4 >
or < 5 >).
Once flash groups A and B have
been set up, you can add group C.
Group C is effective in eliminating
shadows in the background behind
subjects.
Basic settings are the same as
for "Autoflash with Two Receiver
Groups" (p.49).
B