For fashion show...cat walk (flash infos needed)

I'm planning to shoot the Montreal Fetish week-end soon, and I was wondering if a light diffuser or mini soft box on my flash is really needed!
And what about a flash bracket so my flash stays on top when I tilt my camera for portrait?
I am using the Canon 6D and my 580exII with 24-70 or 50 1,4

I wanna keep the ISO as low as possible and popping a flash cause sometimes the light are in the back of the model!!!!


What is your toughest on that?

IF you are going to be close, then I'd suggest a large Rogue Flash bender, or some variation of that.

Anything else.. or if you are far away... well, I'd stick with bare flash. Spot meter with the center point, and use the lock for exposure so you balance it a bit better when the lights are behind.

Light diffusers work well in rooms with white walls and ceilings, if you don't have walls or ceilings close, you are loosing light to the air.. can't bounce back on anything - so not a good idea, eats batteries, may overheat the flash.