SP AF300mm F/2.8 LD (IF)
Model 360E

Tamron's fast telephoto SP AF300mm F/2.8 LD (IF) delivers the remarkable and exacting performance demanded by professionals, with the following features:

• Two large LD (Low Dispersion) elements in the front lens group provide high contrast and crystal-clear image quality from the full open aperture.
• Internal Focusing maintains optimum holding balance since the lens' overall length remains constant during focusing.
• The Floating Focusing System improves optical performance especially at close shooting distances.
• Nine specially-shaped aperture blades form a nearly perfect circle to create excellent background blur for outdoor portraits.
• The true value of this lens is apparent when photographing sports action, low-light theatre performances, and wildlife.

Changeover mechanism for focusing ring
Switching between AF and MF is easily accomplished by sliding the focus ring back and forth. Manual focus is smooth and precise with the focusing ring.

The Canon version provides an easy-to-use AF/MF focusing ring, rear filter insertion frame that is compatible with the standard accessory circular polarising filter and with the ring rotation capability from outside the lens, and detachable tripod mounting stand.

SPECIFICATIONS

NOMENCLATURE

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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