AF28-200mm F/3.8-5.6 XR Di LD Aspherical [IF] Macro
Model A031

In 1992 Tamron's AF28-200mm was the first generation of a new genre of high-power zoom lenses for popular use. The AF28-200mm Super XR (Model A03) made innovative use of XR (Extra Refractive Index) glass to achieve a remarkably lightweight, compact product which won wide acclaim and consolidated Tamron's position as the early pioneer in the development of high-power zoom lenses. This latest AF28-200mm incorporates the Di optical system of improved multi-coating for digital SLR cameras as well as film cameras, further enhancing its ease of use and popularity.

MAIN FEATURES

Internal surface coating reduce ghosting and flare
By employing internal surface coatings (i.e. multiple-layer coatings on cemented surfaces of plural elements) and new multiple-layer coating technology on ordinary elements, ghosting and flare due to reflections that occur when light enters through the front element and reflections caused by the imagers themselves are reduced to the absolute minimum. Moreover, upgraded advanced quality control has raised the level of resolution performance standards, preventing flare due to aberrations, resulting in a high-power zoom lens suitable for photography with digital SLRs.

Ease of use and compact size
A 7x magnification power is now available when used with digital SLR cameras. This marks an extension of the intrinsic convenience of digital cameras, which allows photo images to be checked on the spot, and to be processed freely on a personal computer. The lens retains the compact size of the previous model, designed for 35mm film, with all the ease of use of a 28-200mm high power zoom lens. The complete package heightens the pleasure of using digital SLR cameras.

Perfect for use with both digital and 35mm film cameras
This lens delivers an ultra-long telephoto zoom range up to a 310mm equivalent on an interchangeable-lens type digital SLR camera, as well as 28mm wide-angle images on a conventional 35mm film SLR camera.

External design shared by all Di-series lenses
The external design uses a metal relief ring with a special process designation on the ring. The result is heightened visibility and a quality design. Additionally, the black coating over the entire lens barrel creates a high-quality, sophisticated look.

SPECIFICATIONS

* Specifications based on Nikon mount.

NOMENCLATURE

Digitally Integrated Design

Di is a Tamron designation that applies to lenses that have been optimised for digital capture using advanced multi-coating techniques and optical designs that assure excellent image quality across the entire picture field. Because of these characteristics, Di lenses provide outstanding performance on cameras with full-frame and APS-C format sensors as well as on 35mm film.

Extra Refractive Index

XR (Extra Refractive Index) glass can bend light rays at steeper angles, thereby decreasing the physical length of the lens while enhancing imaging performance by minimising optical aberrations. This has allowed Tamron to develop a line of shorter, smaller-diameter, lighter lenses without sacrificing lens speed, actually upgrading image quality compared to older designs.

XR glass is costlier than conventional glass but it yields enhanced optical power distribution, making possible many of the outstanding and innovative lens designs that bear the XR designation.

Low Dispersion

Chromatic aberration occurs when a lens element refracts different wavelengths of a ray of light – its rainbow colours – at very slightly different angles. This results in the 'colour fringing' that reduces the sharpness of an image. LD elements are made from special glass materials with extremely low dispersion indices (i.e. the refraction of a ray of light into rainbow colours is extremely narrow). Thus they effectively compensate for chromatic aberration at the centre of the field (on axis), a particular problem at long focal lengths (the telephoto end of the zoom range), and for lateral chromatic aberration (toward the edges of the field) that often occurs at short (wideangle) focal lengths. Although costly, LD glass materials result in clear, vivid image quality.

Aspherical

Tamron uses several hybrid aspherical lens elements in its lenses bearing the Aspherical designation. These innovative optics achieve the ultimate in image quality while producing lenses that offer remarkable zoom ranges in extraordinarily compact packages. These cutting-edge advances have advanced the state of optical design by virtually eliminating spherical aberration and image distortion from Tamron's high-power-zoom series.

As one hybrid aspherical lens element can take the place of multiple elements without compromising performance, remarkably compact long-range lenses can now deliver a uniformly high level of image quality across all focal lengths and apertures.

Internal Focusing

Tamron's internal focusing (IF) mechanism provides numerous practical benefits to photographers including:

• a non-rotating front filter ring that facilitates the positioning of polarising and graduated filters
• more predictable handling because the lens length does not change during focusing
• a much closer minimum focusing distance (MFD) throughout the zoom range
• improved optical performance by minimising loss of illumination at the corners of the image field (vignetting)
• suppression of other aberrations that become more troublesome at different focusing positions.

Specifications, design, product name and standard accessories may differ by country or area. While every effort has been made to ensure accuracy, these matters are subject to change by the manufacturer without notice or obligation.

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