I plan to buy a 430 or a 580. It will be used for car shows and drag racings pics and also for pics at night clubs. Which flash would be better for me? Also when I take pics in the P mode or any mode that am taking pics at night, the stock flash from the camera flashs like crazy, then after it adjects to the subject it takes the pic, does anybody know how I can stop the stock flash from flashing wildly before it takes the pic or does it stop after getting a external flash?

