The Canon ST E2 Speedlite Wireless Remote Transmitter is designed for photographers who want to control off camera flash lighting without using a master flash on the hot shoe. It allows wireless optical control of compatible Canon Speedlites, making it ideal for portraits, studio style setups, product photography and controlled indoor environments. This unit suits photographers who want clean on camera setups while still using Canon’s E TTL flash system.
Key Features and Real World Performance
The ST E2 functions as an on camera master unit, sending optical control signals to compatible slave Speedlites. It supports E TTL flash metering and ratio control between two groups of slave flashes, adjustable across a six stop range. In real world use, this allows you to balance key and fill lights quickly without touching each flash individually.
Because it uses optical transmission, it works best indoors or in shaded environments where line of sight can be maintained. The compact size and low weight mean it adds very little bulk to your camera, which is particularly useful for tripod based work or longer portrait sessions.
Pro’s and Con’s
Pros
Enables wireless E TTL flash control without a master flash
Supports ratio control of two flash groups
Lightweight and compact design
Simple integration with compatible Canon Speedlites
Keeps the camera hot shoe clear of bulky flash units
Cons
Optical system requires line of sight
Limited to two flash groups
Not compatible with Speedlite 220EX
Less reliable outdoors in bright sunlight
Why We Like This Transmitter at YPC Outdoors
At YPC Outdoors, we like the ST E2 for its simplicity and reliability in controlled shooting environments. For portrait and product work indoors, it provides dependable flash ratios without adding extra weight or visual clutter to the camera. It is a straightforward solution for photographers who prefer Canon’s native E TTL behaviour without moving to more complex radio systems.
Alternatives Worth Considering
If you are considering similar options, you may also look at:
Canon ST E3 RT for radio based wireless control
Canon Speedlite 600EX II RT used as a master unit
Godox XPro C for third party radio triggering
Each alternative offers different strengths depending on range requirements and lighting complexity.
Comparisons with Similar Transmitters
Compared to the Canon ST E3 RT, the ST E2 uses optical rather than radio transmission, making it more limited in range but simpler to operate. Against using a Speedlite as a master, the ST E2 keeps the setup lighter and avoids unwanted on camera flash output. It is best suited to indoor or studio style workflows.
Tips for Using the Canon ST E2 Correctly
Ensure clear line of sight between transmitter and slave flashes
Use indoors or in shaded locations for best reliability
Assign flashes into two groups before shooting
Use ratio control to balance key and fill lighting quickly
Position flashes carefully to avoid blocked optical signals
Full Technical Specification
Device type: Optical wireless flash transmitter
Flash control system: Canon E TTL
Flash groups: Two controllable groups
Exposure ratio range: Six stop range
Compatibility: Canon Speedlites except 220EX
Use mode: On camera master unit
Dimensions: 6.2 x 8 x 5.1 cm
Weight: 100 g
Product colour: Black
Frequently Asked Questions
Can the Canon ST E2 trigger flashes wirelessly?
Yes, it controls compatible Speedlites using optical wireless signals.
Does it support E TTL flash metering?
Yes, full E TTL support is provided.
How many flash groups can it control?
It controls two groups with adjustable ratios.
Does it emit flash light itself?
No, it only transmits control signals.
Is it suitable for outdoor use?
It can be used outdoors but works best indoors or in shaded conditions.
Is it compatible with all Canon Speedlites?
It is compatible with most models except the Speedlite 220EX.
Does it require batteries?
Battery type is not specified by the manufacturer.
Can it replace a master flash unit?
Yes, it functions as a master controller without flash output.
Is it lightweight?
Yes, it weighs approximately 100 g.
Is this suitable for studio photography?
Yes, it works well in studio and controlled lighting environments.
Buyer’s Guide
If you primarily shoot indoors and want a clean, lightweight way to control multiple Canon Speedlites, an optical transmitter like the ST E2 is a practical choice. Focus on line of sight placement and group balance rather than maximum range. For photographers who do not need radio triggering, this unit offers a simple and effective way to manage E TTL lighting setups.
Looking for more options?
Browse our full range of Camera Flashes for other great choices to suit your space, goals, and budget.
