Canon Speedlite Transmitter ST-E3-RT Wireless TTL Flash Controller

Availability: In stock


Features Highlight
- Compact Radio transmission wireless flash master control
- Supports E-TTL II / E-TTL autoflash, Auto External Flash Metering, Manual Flash and Stroboscopic Flash
- 15-channels in 2.4GHz frequency with 10000 radio transmission ID to avoid interference
- Maximum radio transmission distance of 30m in all direction and controls up to 5 groups*1 and 15 slave units
- Supports 2-way communication between master and slave units; allow transmission of slave units' status and operation from slave units
- Supports Linked shooting*2 and remote release function*2
- Dot-Matrix LCD panel to display more flash settings information
- Speedlite control with EOS Digital SLR Camera's menu*3
- High Strength Metal mounting foot
- Improved quick locking mechanism with “dust wipe mechanism” and “variable contact pressure” design
- Implements 2-line transmission for important signals transmission
- Dust and water resistance# equivalent to EOS-1D Series cameras



On-camera Speedlite Transmitter

Compatible cameras

EOS type-A camera compatible with E-TTL II/E-TTL autoflash

Radio Transmission Wireless Function

Exposure control type

E-TTL II/E-TTL autoflash, manual flash, stroboscopic flash, auto external flash metering*1


IEEE802.15.4, ARIB STD-T66


2405 - 2475 MHz

Modulation system

Primary modulation: OQPSK, secondary modulation: DS-SS


Auto, Ch. 1 - 15

Wireless radio ID

0000 - 9999

Slave unit control

Up to 5 groups*2 (A/B/C/D/E), up to 15 units

Transmission distance (Approx.)

* When there are no obstacles or obstructions between the master unit and slave unit, and no radio interference with other devices
* The transmission distance may be shorter depending on the relative positions of the units, surrounding environment and weather conditions

Flash ratio control

8:1-1:1-1:8 in ½-stop increments (A:B)

Flash exposure compensation

±3 stops in 1/3- or 1/2-stop increments


±3 stops in 1/3- or 1/2-stop increments (when used with flash exposure compensation)

FE lock

Press the camera’s <M-Fn>, <FEL> or <*> button

High-speed sync

Provided *2

Manual flash

1/128 - 1/1 power (1/3-stop increments)

Stroboscopic flash

Provided (1 - 500 Hz)

Slave-ready indicator

The flash icon lights on the master unit’s LCD panel, slave unit’s AF-assist beam emitter blinks, flash-ready lamp lights

Flash exposure confirmation

Flash exposure confirmation lamp lights

Shutter speed limitation

No *2 (However, for camera that released before 2012, the maximum shutter sync speed must be set one-step slower)

Modeling flash

Fired with camera’s depth-of-field preview button

Remote release function


Linked shooting


Power Source

Internal power source

Two size-AA Alkaline/Ni-MH batteries

Radio transmission wireless shooting time

Approx. 10 continuous hours
(when using size- AA alkaline batteries)

Power saving

Power off after 5 min.of idle operation


Custom Function

8 (19 settings)

Personal Function

3 (5 settings)

Camera-controlled Speedlite Transmitter

Supported *4

Dust and water-resistance

Yes (with EOS-1D series camera)

Dimensions (W x H x D)(mm)

67.4 x 61.5 x 77.4
(excluding the dust- and water-resistant adapter)

Weight (without batteries) (g)



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