Canon has announced a new Version 2 of their ST-E3-RT trigger for controlling Canon speedlights off-camera. If you were hoping for some massive upgrade, though, you’re in for a little disappointment. According to what I can see, it basically only adds only three new features over the original ST-E3-RT released in 2012. And not for everybody.
The first is that you (finally) get to be able to shoot rear curtain sync with your wireless Canon speedlights (if your camera is 2020 or newer and not an 850D/T8i). You get a minimum power setting that now goes down to an insane 1/8192 power (but only with the new EL-1 speedlight). And you get a new FE memory feature, allowing you to lock in E-TTL flash exposure levels (with everything).