Canon EOS 80D Instruction Manual page 253

Creative Wireless Flash Shooting
Flash exposure compensation

When [Flash mode] is set to [E-TTL II], flash exposure compensation
can be set. The flash exposure compensation settings (see below) that
can be set vary depending on the [Wireless func.] and [Firing group]
settings.
FE lock

If [Flash mode] is set to [E-TTL II], you can press the <A> button to
perform FE lock (p.232).
Flash exposure compensation
The set amount of flash exposure

compensation will be applied to the
built-in flash and all the external
Speedlites.
2 exp. comp.
Flash exposure compensation is

applied only to the built-in flash.
1 exp. comp.
The set amount of flash exposure

compensation will be applied to all
the external Speedlites.
Wireless Flash PhotographyN
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