Tamron 17-50mm f/2.8 SP AF XR DI-II LD AF-D Lens

Description: Tamron SP AF 17-50mm f/2.8 XR DI-II LD AF-D Camera Zoom Lens

Designed to be used exclusively with digital cameras containing smaller-size image sensors, the Tamron 17-50mm lens is perfect for many situations. The fast aperture of f/2.8, for instance, delivers a natural appearing out-of-focus bokeh effect for portrait images and other intimate situations. A high performance optic that provides simply amazing contrast and color with it's LD glass and big f/2.8 aperture. It features aspherical elements which deliver the ultimate crispness you have come to expect in a pro quality lens featuring a very compact, small size. it also includes a flower petal shaped lens hood created to yield the highest contrast without vignetting. and Includes a 6 year warranty from manufacturer.

The faster shutter speeds, a consequence of the big maximum aperture, also produces a wider photographic representation to augment your photographic enjoyment. As a consequence, the lens lays claim to one of the better close-up photographic performances in the fast standard zoom lens class, while the big aperture of f/2.8 extends through the entire zoom expanse to guarantee stress-free photos at every focal distances and lengths. The 17-50mm delivers an of 26-78mm approximate 35mm equivalent on DSLR cameras featuring24mm x 16mm and smaller image sensors.

Nov 19, 2011

Di-II Series Design
Design has been improved by adding a gold-colored band between the focus and zoom rings to enhance the appearance and make it stand out as a Di-II lens. The rubber patterns of the zoom and focus control rings have been improved at the same time to compliment the digital camera design style and to provide better handling. Di-II Lenses are designed for digital SLR cameras with smaller imagers  

• Low Dispersion lens elements
(LD Glass to reduce chromatic aberration for sharper images) Aspherical - contains aspherical elements (compensates for spherical aberration and distortion, making for better performance with fewer elements (and As a result allowing for smaller, lighter lenses)

• XR Technology. Extra Refractive Index Glass (reduces lens size). The first most important reason that the lens is so compact is the use of high refractive index glass. That is, XR glass. High refractive index glass bends light more than normal or lower refractive index glasses. Normally, glass material having a refractive index of more than 1.69 is called high refractive index glass. In the A03 optical system, glass material having a refractive index of more than 1.69 is used in the front group. In addition, refractive index of the whole optical system is enhanced. By using high refractive index glass in the front group, we could make the elements in the first group thinner, and reduce one element in the second group. This made the overall length of the whole optical system shorter

This lens is pretty sharp at all focal lengths, even wide open, but contrast does go up a little when stopped down from f2.8 to f4. the Tamron 17-50mm f/2.8 XR Di II Lens is very similar to the the Sigma 18-50mm f/2.8 EX DC Lens. These lenses are more similar than different. They are very similarly sized and shaped and they function very similarly.

• Flower Shaped Lens Hood
• Lens Caps

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