In my tutorial, How to Photograph Volleyball, I mentioned that I like to shoot spikers at from a 30 to 80 degree angle to the net. Here are some shots taken a week ago. Look at these left outside hitters and middles. Check the angle of their heads and ask yourselves, What angle to the net will give the best opportunity to see their faces at the spike?
If your angle to the net is less than 30 degrees, you risk being blocked out by the spiking arm. Generally, the spiker's eyes will not go past 80 degrees on the follow through. Obviously, these rules must be adjusted for a left handed spiker. Since I typically won't move to shoot the spiker on the right side, I often shoot from about a 60 degree angle. Try different angles and see how your results work.
Philip S. Zivnuska