Cambridge World, Item Details: Tokina 28-80mm f/2.8 AT-X 280 AF PRO

AT-X 280 AF PRO, a 28-80mm auto-focusing zoom lens with a constant aperture of f/2.8. This lens is the latest addition to Tokina's highest quality AT-X AF PRO series lenses and is going to be available in late April, 2000. Glass The AT-X 280 AF PRO is

constructed with high quality optical glass multicoated lens elements created by Hoya Corporation, the world's largest manufacturer of optical glass. Two Aspherical lens elements and one SD (super low dispersion) glass element are employed in the optical

design to insure critical sharpness across the film plane. One aspherical element is molded as one piece of optical glass created with technology pioneered by Hoya. The other is a hybrid aspherical element. Focusing An internal focusing mechanism with

a Tokina Focus Clutch Mechanism gives this lens fast auto focus. The focus clutch feature, a signature of the Tokina PRO series lenses, allows the manual focus ring to be snapped forward to an auto focus position. This disengages the ring from the focus

gearing and provides a faster, smoother auto focus operation. When snapped back to the manual focus position, the ring is damped for a smooth manual focus action not normally found in today's auto focus lenses. A refinement of the focus clutch mechanis

m has been incorporated in the AT-X 280 AF PRO Nikon and Canon mount, so that now the lens' focus ring can be snapped back to the manual focus position at any time. This improvement means it is not necessary to change the AF/MF switch (on the body with Ni

kon or the lens with Canon) every time the lens is changed from auto focus to manual focus mode. Internal focus means the 77mm filter threads do not move during focusing. The advantage is when a special effects filter is used it is not necessary to rea

djust the position of the filter every time the focus is changed. A window has been added to the AT-X 280 AF PRO that shows a distance scale. This makes it possible to tell the focusing distance, regardless of the actual setting of the focus mode. Like

the rest of the lenses in the AT-X series, the AT-X 280 AF PRO is what is commonly referred to as a parfocal lens. This means that if focus is achieved at 80mm, then the lens is zoomed back to 28mm, the subject will still be in focus.