In ball games one cannot direct ones gaze at the ball all the time, because one must also judge other aspects of the game, such as other players positions. We wanted to know whether there are times at which obtaining information about the ball is particularly beneficial. We recently occluded vision at random times and found that people could catch successfully if they saw any part of the balls flight except the very end, when sensory-motor delays make it impossible to use new information. It was even enough to see the thrower propel and release the ball, so it is not even essential to see the balls flight. Nevertheless, there may be a time that is particularly useful. Here we gave six catchers the chance to choose when they look at the ball. A catcher and a thrower continuously threw a ball back and forth. We recorded their hand movements, the catchers eye movements, and the balls path. While the ball was in the air, approaching the catcher, information was provided on a screen as to the peak height of the ball that the catcher had to try to achieve when throwing the ball back to the thrower. This information disappeared just before the catcher caught the ball. Most catchers mainly looked at the screen until the information they needed was provided, and then looked at the ball from then on. However, some mainly first looked at the ball and then at the screen, probably switching once they thought they had enough information to catch the ball. At least two catchers switched between these strategies. The balls peak heights when thrown back confirm that the catchers saw the information on the screen. Thus there does not appear to be a critical time for seeing the ball.
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