Battery
The transmitter needs two size-AA batteries (not provided). The
receiver draws power from a flash through the flash’s Wireless
Control Port. Slide the battery compartment cover of the
transmitter and insert the batteries.
Power Switch
Turn the transmitter on by sliding the ON/OFF Switch to ON. The
LCD display will then light up.
Low Battery Indication
When the battery power (<2.2V) gets low, is shown on the
LCD display. Please change batteries as low battery power
leads to no flash or flash missing in case of long distance.
Turn the transmitter off to save power if it will not be used for
an extended period.
Channel
S1
S2
S3
S4
1
0
0
0
0
2
1
0
0
0
3
0
1
0
0
4
1
1
0
0
5
0
0
1
0
6
1
0
1
0
7
0
1
1
0
8
1
1
1
0
Power-Control Group Selection
Both the transmitter and the receiver have a 16-grade Power-
Control Group Select Dial (hereinafter referred to as Dial). With
these 16 grades, you can wireless control at most 16 flash
groups in terms of the following functions: adjusting the power
ratios and turning on/off the buzzer and the modeling lamp or
the AF-assist beam, as well as flash triggering.
Attach the receiver(s) on multiple flashes/one flash and set the
Dial of each receiver to the same grade. This is a flash group.
Then attach the transmitter on the camera's hotshoe or hold it
in hand, and set the Dial to the same grade as that of
receiver(s). After settings, the flashes will be under your
command.
The transmitter and the receiver must be set to the same
channel for wireless control. Otherwise, the receiver does not
respond.
The relationship of
PRO AC/ST-I
and
ST-III
wireless
trigger
system:
PRO AC/ST-I
(Code Switch)
ST-III
(Display Screen)
PRO AC/ST-I
(Code Switch)
ST-III
(Display Screen)
ON
CH01 CH02 CH03 CH04 CH05 CH06 CH07 CH08
CH09 CH10 CH11 CH12 CH13 CH14 CH15 CH16
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
Note:
When use
ST-III
series transmitter in combination with
PROAC/ST-I
series receiver, please set the transmitter to M mode.
PROAC/ST-I
cannot
receive the
parameters that emitted by the transmitter in TTL and M mode.
Channel
S1
S2
S3
S4
9
0
0
0
1
10
1
0
0
1
11
0
1
0
1
12
1
1
0
1
13
0
0
1
1
14
1
0
1
1
15
0
1
1
1
16
1
1
1
1
Power-Ratio Display Mode
The trigger set has 3 modes to display a flash’s power ratio.
1.
1/128~1/1:
widely adopted in most shoe mount flashes.
2.
5.0~10:
adopted in some studio flashes.
3.
1.0~7.0:
adopted in some studio flashes
The 3 display modes can be switched over by pressing the Set
Button and holding for 2s.
Channel Select Switch
The trigger set provides 16 channels for communication. Set the
transmitter and the receiver to the same channel before use.
Check the following table for channel settings: