Tamron has released its AF55-200mm F/4-5.6 Di II Macro LD (Model A15), a new telephoto zoom designed for digital SLR cameras with image sensors smaller than 24mm by 16mm. The zoom covers the focal length range equivalent to 85-310mm when converted to a 35mm format. The lens will allow owners of digital SLRs fitted with standard zoom lenses to produce the pulling and compression effects particular to telephoto lenses.

Because the optical system is designed for digital cameras, the image circle is smaller. The new 55-200mm zoom lens has a minimum focus distance of 37.4 inches over the entire zoom range, the top level of the closest focusing distance among tele-zoom lenses. The maximum magnification ratio of f=200mm is 1:3.5, for convenient close-up photography. The nine-blade diaphragm construction provides naturally blurred background effects when using the shallow depth of field of a telephoto lens or in close-up photography.

The lens features a mount made of durable, lightweight plastic molded around a stainless steel core. The lens mount portion weighs 70 percent less than a brass-made mount. The compact lens measures 3.3 inches and weighs 10.4 ounces.The list price is $281.