Kevin McAbee is a software and web developer for the SAS Institute, in Cary, North Carolina. He spends his free time studying astronomy, brewing beer, and enjoying the great outdoors via rock climbing, backpacking, and amateur photography. In the fall of 2012, he joined the In Saturn's Rings IMAX film project as an image processor and programmer.
Cassini took 14 images of Saturn's north polar vortex on November 27, 2012 over a period of many hours as the planet rotated beneath it. The 14 images have been processed to remove the geometric effects of Cassini's oblique viewpoint and of Saturn's rotation, holding the outer bright ring of white clouds fixed. With these motions removed, you can see individual vortices rotating and shearing, and the central clouds rotating faster than the outer ones.