Canon off camera flash

[JABB]

I have a 550EX flash and want to add 1 or 2 flashes into the mix. Am I better going for slave canon flashes ( if so, which ones work? ) or am I better using wireless triggers?
I presume if using the wireless, I could use any flash going? Some of the old Canon EZ range seem cheap, but can I use them.
Camera is a 40D
If you have gone down any of the above routes, please recommend kit!

[RobDickinson]

JABB said:

I have a 550EX flash and want to add 1 or 2 flashes into the mix. Am I better going for slave canon flashes ( if so, which ones work? ) or am I better using wireless triggers?
I presume if using the wireless, I could use any flash going? Some of the old Canon EZ range seem cheap, but can I use them.
Camera is a 40D
If you have gone down any of the above routes, please recommend kit!

For a master it will have to be the 550 (or a 580, or an st-e2 or a 3rd party master).

For ettl slaves you want the 420ex ,430ex, more 550/580's or some 3rd party flashes.

Sigma 530 super or nissin di866 both work in the canon wireless system, I have the nissin.

ETTL has its uses, it can work out what it thinks is right (like camera meetering this isnt always right), but in changing conditions its much easier to use than manual.

If you can controll the conditions or take time to get things right then manual can work better.

If you go radio wireless then yes any flash will do (within reason, needs the right trigger voltages and to work with the trigger, and realy could do with power control).

ETTL uses a (pre)flash to controll the flashes, this obviously has restrictions on how it triggers (not round corners, distance etc).

Something like the yong-nuo rf-602's can trigger flashes (and work as a remote release!) up to 100m away.

[JABB]

So if I bought some remote triggers and, say, 420EZ or 430EZ flash guns, I would have a decent, controllable rig?

[RobDickinson]

Not sure the EZ's would ettl if you wanted to use the 550 as comander but yeah I think that should all work ok.

I'm not a flash expert tho.

[Xerstead]

JABB said:

So if I bought some remote triggers and, say, 420EZ or 430EZ flash guns, I would have a decent, controllable rig?

Yes, with emphasis on controllable. With the basic wireless triggers each flash would need to have it's power output set manually.
There are more expensive options like Pocket Wizzards which I believe can controll power output remotely as well; similar to Canons own sytem with the master flash controlling the others.