Tokina AT-X 28-70mm f/2.8 is an exceptionally fast standard zoom lens with razor sharp optics and constant lens speed for most autofocus 35mm SLR cameras. The internal focusing lens employs a constant f/2.8 aperture enabling focusing and shooting in low light conditions. This lens features enhanced multi-coating improve contrast while reducing flare and ghosting. In addition, the lens features One-touch Focus operation, 16 elements in 12 groups, eight blade diaphragm, 75.3-34.3° viewing field, 0.7m close focusing distance and 72mm filter thread.