I initially took the picture with them just backlit, and started to panic when the light from the back reflected off the wood and they were lit in a deep red (blood red).
Luckily I had a gary fong lightsphere sitting ontop of my backpack, and I had my assistant tuck it infront and above them with another 580ex II set on ETTL and -3EV. Finding the correct exposure was super hard because the flash made her dress explode so bright. So I cranked up to like f11 and it worked out beautifully.
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Clubbing Baby Seals since 84' *club club*
British Columbia, Canada.