POWER !Have you thought about using a flashlight instead? I'm still wondering why I paid a couple hundred dollars for something that just blinks light when I could've done the same job with a zebralight with a frosted lens.
The Canon 580EX II can put out about 75 Ws of energy and the flash tube produces about 40 lm/W. Assuming this full power is dumped in about two thousandth of a second, the peak light output is about 75 Ws * 40 lm/W / 0.002s = 1.5 million lumens! You will need about 3000 Zebralights each putting out 500 lumens to produce the same visual effect. Even with those you can't match the CCT and CRI of the flash light
On the other hand the new 660 XRT (no need to buy them) They are a LITTLE bit more powerfull and yet MUCH MORE expensive in comparison to the EXII generation.