Canon EOS 7D Mark II (G) Instruction Manual page 283

Manual Setting of the Flash Output for Wireless Flash Shooting
When [Flash mode] is set to [Manual flash], flash exposure can be set
manually. The flash output settings that can be set ([1 flash output],
[Group A output], etc.) vary depending on the [Wireless func.] setting
(see below).
Built-in flash will be output at 1/4 - 1/128 when 0+3 is set.
Wireless func.: 0
Firing group: 1All
The manual flash output setting is
applied to all the external Speedlites.
Firing group: 1(A:B:C)
You can divide the slave units into
Groups A, B, and C and set the flash
output separately for each group.
Wireless func.: 0+3
Firing group: 1All and2
You can set the flash output
separately for the external
Speedlite(s) and built-in flash.
Firing group: 1(A:B:C)2
You can divide the slave units into
Groups A, B, and C and set the flash
output separately for each group. You
can also set the flash output for the
built-in flash.
Using Wireless FlashN
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