I must say I truely like my two Sigma DG Super 500 flashes. They have been most reliable. However, they do not have any type of input for external power like the Canon 550EX. In the past I've heard of those who have built rechargable packs for their flash (not the Sigma, but others). Can someone help me out here? Just point me to a sight that has directions on what to do. I'm looking for this to hopefully gain rapid flash recycle times.
Thx

