Trying to understand off camera flashes

if you are going with some vivitar flashes, you won't need the Flexttl system by pocketwizard (or whatever it's called)

what would i need to trigger the flashes then

you'll need triggers of some kind, and whatever you get will depend on your budget.

>implying you can afford something like pocket wizards, because you suggested them in your OP, i'd say either Pocket Wizard Plus 2's or Cybersyncs

>implying you are on a more budget friendly route, because you suggested getting vivitars in your OP, i'd say either the Yonguno RF-603 system or the 602's. The 603's are the newer version and are crazy sweet and like $25 bucks for a pair.

You will need a wireless transceiver for your camera hot-shoe and a couple of receivers, one for each flash. Check out www.strobist.com and that'll be about all you need for info.

**Nikon** (canon is the same)
off camera flashes are essential to my part time job. i digitally reproduce images.
i have three of these. they work great but are a little expensive.

and 2 nikon SB-900 strobes.
just that has cost about $1,700 (SB-900 = 500x2 + PW = $350x3 - minus discount) CAD
so its dece expensive.
for you, the TT5s will be the money and the vivitars will be about $100 each.
dont go for the mini because with the flex you can buy a wire for your camera and fire it wirelessly (if you cant already) more functionality if you can deal with a larger transmitter.

if you have any questions regarding outdoor, indoor, flash power, etc you can PM me for questions.

Vouch for the 603's. They're perfect.