Canon Speedlite 430EXIII-RT Instruction Manual page 61

Slave C flash exposure
compensation amount
Group Control
Firing group A
f f
For example, if you set a firing group with three slave units to <a>,
the three units are treated and controlled as a single firing group A with
a large flash output.
To fire the three firing groups A, B, and C at the same time, set
<6>. With the <5> setting, firing group C does not fire.
If you shoot with firing group C pointing directly toward the main subject,
overexposure may result.
The flash ratio of 8:1 to 1:1 to 1:8 is equivalent to 3:1 to 1:1 to 1:3 (1/2-stop
increments) when converted to the number of stops.
5: Wireless Multiple Flash Shooting with Flash Ratio
Set the flash exposure
4
compensation amount for slave C.
Set it by operating the master.
Set the amount as necessary.
Press <8>.
Turn <9> to select the flash
exposure compensation amount
symbol for C, then press <8>.
Turn <9> to set the flash exposure
compensation amount, then press
<8>.
If you need more flash output or wish to
perform more sophisticated lighting, you
can increase the number of slave units.
Simply set an additional slave unit to the
firing group (A, B, or C) whose flash
f
output you want to increase. You can
increase the number of slave units up to
15 units in total.
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