Canon EOS 80D - Manual (Page 254)

Wireless Flash PhotographyN
254
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).
Wireless func.: 0
 Firing group: 1All
The manual flash output setting is
applied to all the external Speedlites.
 Firing group: 1 (A:B)
You can set the flash output
separately for slave groups A and B.
Wireless func.: 0+3
 Firing group: 1All and 2
The flash output can be set
separately for the external
Speedlite(s) and built-in flash.
 Firing group: 1 (A:B)2
You can set the flash output
separately for slave groups A and B.
You can also set the flash output for
the built-in flash.
Setting the Flash Output Manually for Wireless Flash Shooting