The first camera manufacturer to integrate radio-based triggering in their flashguns, Canon have unveiled the Speedlite Transmitter ST-E3-RT and Speedlite 600EX-RT. Sending information via 2.4GHz signal rather than infrared, the new system can operate at up to 30 metres even in bright sunlight and without line-of-sight.
The Speedlite Transmitter ST-E3-RT is an E-TTL II commander unit that sits on the hotshoe of your Canon DSLR, powered by two AA batteries. It has a full LCD screen and can control up to 15 remote devices. These can include the new 600EX-RT flashgun or a remote Canon camera connected to a second ST-E3-RT unit. Unfortunately there is no autofocus-assist lamp. The device is weather sealed “to the same degree as professional EOS cameras”.
Since Canon is using the universal licence-free 2.4GHz frequency, in common with many third party triggers, the same models can legally be distributed worldwide, unlike PocketWizard which must make a different version for each market.
The 600EX-RT is Canon’s latest flagship Speedlite with wireless triggering built in. It can act as a slave or be master to up to 15 remote flashes and cameras. The old infrared system can still also be used. As a remote flash, the 600EX-RT can be put into one of five groups when triggered by radio or one of three groups using infrared E-TTL II.
The guide number (GN) is 60 (at 200mm zoom setting), adjustable down to 1/128 of full power in 1/3 stop levels. The flash head tilts, swivels and zooms from 14-200mm. At full power, the recycle time is 3.3 seconds.
Where to buy
The Canon RT system is slated to be ready at the end of March at the following prices.
- Speedlite 600EX-RT:  $629.99, €699, £679.99 (Pre-order)
- Speedlite Transmitter ST-E3-RT: $470, €320, £309.99
Could Canon’s announcement make third-party TTL triggers such as the PocketWizard FlexTT5, Pixel King and Phottix Odin redundant? Let us know your thoughts below.