SP AF180mm F/3.5 Di LD [IF] 1:1 Macro
Model B01

This lens employs an IF (Internal Focusing) system that maintains the overall length of the lens during focusing. Two LD (Low Dispersion) glass elements effectively compensate for chromatic aberration. High-contrast, outstanding image quality is combined with a soft out-of-focus background effect. An AF/MF one-touch switchover mechanism is built into the focus ring (Canon & Nikon mounts). The SP (super-performance) label designates high performance through outstanding design specifications.

FEC (Filter Effect Control)
The new FEC (Filter Effect Control) function enhances operational ease of use of polarising filters. It allows rotation of the filter to the desired position while the hood is attached: turning the FEC ring in turn rotates the filter mount.

SPECIFICATIONS

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.

Super Performance series

Tamron SP (Super Performance) series is a line of ultra-high-performance lenses designed and manufactured to the exacting specifications demanded by professionals and others who require the highest possible image quality. In creating SP lenses Tamron’s optical designers put their foremost priority on achieving superior performance parameters – they are all designed to a higher standard with little regard for cost constraints. As a result, Tamron lenses bearing the SP designation feature impressive and innovative designs that have established an enviable reputation for excellence among those knowledgeable photographers that demand the very best.

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.

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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