Canon 500mm f/4 USM L IS

An outstanding lens that works beautifully with the Canon 1.4x and 2x extenders. It can focus as close as 18 feet and shares its weather-resistant gaskets and sealed focusing rings with Canon's other Image Stabliized lenses. Image Stabilizaton adds a new dimension in this lens' usefulness, even in low light situations. I sold this lens in October of 2002 and bought the 600mm version in December of 2002.