That's all well and good, but who's the girl behind the Canon lens?
I marvel at the Sigma since I just bought a 200-500mm f/5.6-6.3 (Tamron) lens. Given the same focal length, it's interesting to see the size difference with the aperture change to constant 2.8! And a note to the author: It doesn't look anything like a surface to air missile launcher. Perhaps an AT-4.