The Canon Speedlite Transmitter ST-E3-RT (Ver. 2) is the industry-standard tool for professional off-camera flash photography. Utilizing a robust 2.4 GHz radio frequency system, it provides reliable wireless communication between the camera and up to 15 compatible Speedlites over distances of up to 30 meters. Unlike traditional optical transmitters, this radio-based system does not require a direct line of sight, ensuring consistent firing even when flashes are placed behind softboxes, around corners, or outdoors in bright sunlight.
Designed for the rigors of professional use, the ST-E3-RT (Ver. 2) features the same dust and water resistance as Canon’s top-tier EOS-1D X series cameras. This updated “Version 2” model introduces critical workflow enhancements, including support for wireless second-curtain synchronization (creating natural light trails) and Flash Exposure (FE) Memory, which allows photographers to lock in a TTL exposure level and instantly switch to Manual mode for consistent repeatability. The dot-matrix LCD panel provides a clear, backlit interface for managing ratios and groups quickly during fast-paced shoots.
Technical Specifications:
- Transmission Type:4 GHz Radio Frequency
- Transmission Range: 30m (360° coverage)
- Channel/ID: 15 Channels / 0-9999 IDs
- Maximum Flashes: 15 units in 5 Groups (A, B, C, D, E)
- Exposure Control: E-TTL II / Manual / Stroboscopic / Gr
- High Speed Sync (HSS): Yes
- Second-Curtain Sync: Yes (Ver. 2 feature with compatible cameras/flashes)
- Power Source: 2 x AA / LR6 Batteries
- Dimensions:4 x 61.5 x 77.4 mm
- Weight: 110g (excluding batteries)
- Mount Material: Metal
