Canon EOS 70DN Basic Instruction Manual page 371

Set ing [E-TTL II meter.] to [Evaluative] is recommended.
Firing a test flash is not possible with the slave unit.
4
Set [Flash mode: E-TTL II].
Set [Flash mode] to [E-TTL II].
5
Set [Wireless func.:0].
Set [Wireless func.] to [0].
6
Set [Channel].
Set the channel (1-4) to the same one
as the slave unit.
7
Set [Firing group:1All].
Set [Firing group] to [1All].
8 Take the picture.
Set the camera and take the picture
in the same way as with normal flash
shooting.
To terminate wireless flash shooting,
set [Wireless func.] to [Disable].
Using Wireless FlashN
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