I shoot a lot of barrel racing. I use 2-3 Einsteins and shoot in manual mode with the strobes set in action mode, 1/200th, usually I set the ISO to around 200-320 to get my best exposure at around f/4 or 3.5. I shoot with my 5DmkIII in servo mode case 2. Use my 70-200 f/2.8L IS II. I use a long throw reflector on my main strobe, usually mounted to the fence in the ally. I shoot barrel #2.
Here is one of my shots.
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