While photographing the birds in my garden, the occasional plane crosses my eye. They are hard to focus on and fly by very fast, but I'm improving and the new (august 2008) stabilized Sigma 150-500 helps. We live in the wild Provence backcountry and flying is unrestricted here, lots of light aircraft fly here, including my neighbor's...The new, 2009, Nikon 500vr really helps...