The engineering behind lenses, especially zoom lenses, is astonishing in its precision and complexity. No time is this more apparent than when you can get a good look at what’s inside a lens. A FredMiranda forum member took apart a bum 17-85mm EFS Canon lens and found it to be full of glass, rings, and other wonderful things. If you cut a lens in half you get the inside picture, but this shows just how many bits are working together every time you twist the focus ring. [via Gizmodo]