Flash Shopping Question

[plentygood]

Now that I have a job I've been looking into a speedlight setup (thank you Strobist!) and I've hit a question that I haven't been able to find the answer to. If I'm radio triggering the flash (PW/ebay), I don't need a master flash right? The transmitter would in short be the master? I wouldn't think so, but I'm just trying to get as much research in as I can. Thanks!

 

[bigalbest]

Yes, with Cactus there is a transmitter for the camera and a receiver for each flash. With PW's you need one for the camera and one for each flash.

 

[plentygood]

Ok, thanks, that's what I thought, but just wanted to make sure before I got more in-depth into the shopping/planning.

 

[Big Mike]

With any wireless system, there is a sender/master and a receiver/slave. The radio triggers (PW/Cactus) are independent and need to be connected to the camera and to the flash.

With the Canon or Nikon system, the wireless features are built into the flash units themselves, but you still need a master to send and a slave to receive.

So yes, you are on the right track.

 

[plentygood]

So I could simultaneously fire two 420ex's (each with a cactus receiver) from a 30D (with a cactus transmitter)? There's no master-capable flash like a 580ex required?

 

[Big Mike]

So I could simultaneously fire two 420ex's (each with a cactus receiver) from a 30D (with a cactus transmitter)? There's no master-capable flash like a 580ex required?

That is correct.

Keep in mind that using radio triggers is different then using Canon's system. Canon uses Infra Red beams to communicate between master & slave. This allows the flashes to function just like they are actually attached to the camera. You can use the auto (E-TTL) flash metering or high speed sync (HSS) and you can control the power of the remote flashes (or groups of them) via the master unit. The problem is that IR isn't always a great method of communication...outdoors for example.

When using the radio triggers; Cactus, Pocket Wizards or Skyports etc...it's a simple radio signal. You can fire the flashes but there is no auto metering...you have to set the power manually. Once you get the hang of it, manual flash control is very consistent and fairly easy...but it does take a while to really learn it.
Radio signals are better than IR and they work well in most situation.

One last thing, the cheap Cactus (E-bay) triggers aren't know to play well with Canon flash units. I have a cactus set and it doesn't really work with my 430EX flash. Luckily, I have a handful of older flash units and the cactus trigger works fine with them.