Take full advantage of all the features on compatible flashes with the third iteration of the Canon Speedlite Transmitter ST-E3-RT. This transmitter simplifies complex lighting setups by facilitating radio-controlled, two-way wireless transmission at distances up to 98.4' among up to five groups or 15 individual Speedlites. Wireless Rear Curtain Synchronization is available for capturing light trails and creating motion blur in your images. An expansive minimum output range allows you to stop down to 1/8192 for very low-light shooting. Another useful feature is FE Memory, which allows you to lock in an E-TTL flash exposure level, even in complex multi-flash setups, and subsequently continue to use it for the same scene or subject. Eight types of custom functions and three types of personal functions are included in the design. The LCD panel and backlit controls allow for easy operation even when you're working in dimly-lit environments.

Wireless Rear Curtain Synchronization    5 Groups or 15 Speedlites, Range: 98.4'    8 Custom Functions, 3 Personal Functions    LCD Information Panel, Backlit Controls

• High-performance hot shoe contacts for reliable information transmission and operation.

• Up to five groups, or 15 individual flashes can be controlled via 1 transmitter.

• Supports E-TTL II Flash, Manual Flash, Stroboscopic, and Auto External Flash Metering.

• Dot Matrix LCD Panel displays all pertinent information simultaneously and backlit control panel for easy operation.

• Eight types of custom functions with three types of personal functions.

• High-performance hot shoe contacts for reliable information transmission and operation.

• Wireless Rear Curtain Synchronization.

• Minimum output range of 1/8192.

• Built in FE Memory so you can lock in an E-TTL flash exposure level.

Related Questions and Answers

Q: 1. Is the ST-E3 version 1 able to be updated by firmware to be used with the new EL-1?

A: No. The unit is not updateable.

Q: 2. Will it work with only 430EX II flashes?

A: The ST-E3-RT is not compatible with a 430 EXII.

Q: 3. Does this have a ttl to manual power setting feature?

A: Yes. The following unit supports the following E-TTL II flash, manual flash, stroboscopic and auto external flash metering.

Q: 4. Many flash remotes now include a button that will take the flash power generated by TTL and provide the manual exposure settings with a press of the button. Does this unit do that?

A: The ST-E3-RT II is capable of setting the firing output within the custom functions.

Q: 5. Are there any third party strobes that work with this transmitter

A: No, the Canon Speedlite Transmitter ST-E3-RT (Ver. 2) is proprietary to Canon's system.

Q: 6. Will this item support shooting in (camera) Manual mode when combined with a EOS 1 DX Mark III and a Speedlite EL-1 or am I limited to Program mode?

A: ***********Please send this to SLR Q&A **************

Q: 7. Will it work with both canon flash and Godox 400pro?

A: No. System will only communicate with canons protocol system.

Q: 8. Does V3 reduce the amount of dropped links to flash units? This is a significant issue with V1 and V2 transmitters.

A: With the new ST-E3-RT III the improved high-performance hot shoe contacts for reliable information transmission and operation address this issue the previous models had yes.

Q: 9. Will Canon ST-E3-RT work with Canon EL-5?

A: Yes, the Canon Speedlite Transmitter ST-E3-RT (Ver. 2) works with the Canon EL-5 speedlight.

Q: 10. Is the ST-E3-RT compatible with the Canon 5D Mk4?

A: Yes. The following unit will communicate with Canon s TTL metering system.