I am trying to take pictures of dogs at full speed at night in horrible light outside. I am using a 30D with a 70-200 f4 L lens and a 580 flash. I can't get rid of the harsh shadows. I'm pretty sure I need at least two more flashes to balance this out (although I do have a problem with placement of one of the flashed blinding the person on the bite side of the dog). Any suggestions on what will help with out breaking the bank. I don't think the ST-E2 will work with the distance.