Questions about Canon Wireless Lighting Setup

[TiCoyote]

I'm thinking about switching from 3rd party flashes to Canons. I photograph weddings with 2 bodies. One has a flash, and the other doesn't. Both have triggers to two flashes on light stands.

I was thinking about this setup:
Body 1: 600EX-RTii
Body 2: ST-E3-RT
Lightstands: 430-EXiii RT.

Am I correct in assuming that the 600 will trigger the 430 via built-in radio?

Also, it looks like the ST-E3-RT costs nearly as much as a 430 flash. Could I use the 600 as one Master on one body, a 430 as the Master on the second body, and then the other two 430s as slaves on the stands?

 

[TCampbell]

The 600EX II-RT and 430EX III-RT can be either master or slave (an ST-E3-RT can, of course, only be a master since it doesn't actually have a flash). Linking is pretty easy. Units just need to be on the same radio channel and using the same ID number. If you want some units to be controlled only by one camera vs. the other... then assign them to use different ID numbers (the factory default ID number is "0000").

You can also take advantage of the group assignment feature. This would let you put your on-camera flash in a group, off-camera flash in a different group, and you can choose if you want "all" groups to fire ... or just one (just off-camera or just on-camera). You can even control ratios... so the off-camera lights could be key lighting and on-camera lights could be fill-lighting, etc.

If shooting weddings with remote speedlites, I'd change that ID number... otherwise you risk a guest using a flash with the default factory ID number triggering your remote slaves.