Originally Posted by
GrumpyDiver
5. External triggers - there are a number of these around. I happen to use PocketWizards, because they are the most flexible ones for my personal needs. I can't comment on how well the less expensive alternatives work, especially for TTL metering (they likely do not support this). I have both the FlexTT5 transceivers that mount the flashes on and a MiniTT1 transmitter I use on the camera. I also use a AC3 Zone controller that mounts on the MiniTt1 (orFlexTT5) and allows me to change the output on the Speedlights right from the camera (either fully via TTL or manual modes, including High Speed Synch functionality).
This is a fairly expensive solution and you need one radio trigger for the camera and one for each flash. This is what I use and I would not use anything else.
PocketWizard has a number of manual triggers (Plus X and Plus III), which are less expensive, but are really best left to Studio flash, which are 100% manual.