Why not invest in a good quality light meter? Then you can take an incident light reading from the position of your subjects. Transfer the readings for Tv and Av to the camera in manual mode and fire away.
It takes too long to transfer information from the light meter to the camera.
During an outdoor wedding like Dan showed, things are popping quickly. There are subjects moving toward the camera, away from the camera, in and out of shadows, ...
About the last thing that I want is one more piece of external gear to slow down the operation. As it is, one camera can "talk to" one flash unit and get something pretty close.
---Bob Gross---

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