Canon Speedlite 430EX - Manual (Page 19)

M
Manual Flash
You can set the flash output from 1/64 power to 1/1 full power in full-
stop increments.
Use a hand-held flash meter to determine the required flash output to
obtain a correct flash exposure. Be sure to first set the camera's
shooting mode to <
Av>
or
<M>.
Press the <MODE> button so
that<M> is displayed.
Set the flash output
Press the <® > button.
The flash output display will blink.
Press the < ® > button to set the
flash output, then press the <® >
button.
Press the shutter button halfway to
see the effective flash range
displayed.
Zoom 50mm
M l/B 1.5"
19