I took the Sigma 70-200 out to the airport this morning (AUS) and had a go at taking some airplane pictures. It was a little late in the morning (approaching noon) and the light was not optimal. Winds out of the north meant that takeoffs were in a bad direction for photography with the sun position, but it made for better takeoff shots, when you usually only get landing shots. It's going to take some practice to figure out the optimal settings for this lens, but initial results are quite good. Stopping the lens down a bit helps. I'll be heading out again Monday morning to shoot the heavies leaving AUS after the USGP. I went last year, and that was by far the busiest day I've ever experienced at this airport.