Pelle Cass takes up to 5,000 pictures, vibrating the camera so much it requires refocusing. This composite was shot at Harvard Stadium. Tennis players go nuts in this image from Cass' digitally manipulated series Crowded Fields. Never mind waiting one's turn. Cass used Photoshop to turn diving championships at MIT into pure mayhem. Cass' images are digital composites crafted from thousands of images. This one depicts field hockey gone haywire at Boston University. Cass works with a DSLR on a tripod, the angle fixed so that every image depicts the same basic scene. What's the point of playing with just one ball, anyway? After attending events like this track meet at Boston University, Cass goes through all his pictures multiple times. He first selects the most compelling figures, then ones that complement them. Cass works with layers and masks in Photoshop to build up the composition, a process that takes up to 80 hours. The result, like this image from Boston College, would make any referee despair.