Canon EOS 7D Mark II (G) Instruction Manual page 281

Fully Automatic Shooting with the Built-in Flash and
Multiple External Speedlites
The built-in flash can also be added to wireless flash shooting explained
on pages 278-280.
The basic settings are shown below. By changing the [Firing group]
setting, you can shoot with various wireless flash setups of multiple
Speedlites complemented with the built-in flash.
[1All and2]
Basic settings:
1
Flash mode
Wireless func. :0+3
Channel
Set [Firing group].
2
Select one of the following: [1All
and2], [1(A:B)2], or [1(A:B
C)2].
With [1(A:B)2], set the A:B flash
ratio and shoot.
With [1(A:B C)2], set the A:B flash
ratio and flash exposure compensation
amount for C, then shoot.
A
[1(A:B)2]
Using Wireless FlashN
: E-TTL II
: (Same as slave units)
C
B
A
[1(A:B C)2]
B
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