I've never shot Track & Field before and want to know what lens works best for Track & Field between the 100mm-400mm f/4-5.6 IS or 70mm-200mm f/2.8 IS. The event time will be in the afternoon with plenty of sun. I'm leaning toward the 100mm-400mm because of focal length and the event is held at noon. On the other hand, the 70mm-200mm is faster, so I'm torn between the two right now. I bring the 1.4x for insurance to use if necessary. Here is what I want to capture.
1. Facial expressions.
2. Lots of close up with runner in entire frame.
3. Lots of close ups with runners close to each other.
4. Close ups with blur effect.
5. Shooting @ 500-1000 max shutter speed.




