The new AF18-200mm F/3.5-6.3 XR Di-II LD Aspherical (IF) MACRO is a high power zoom lens for exclusive use with digital (APS-C size) SLR cameras that inherits the product concept of the existing AF28-300mm F/3.5-6.3 XR zoom lens. Even two years after its introduction, the current AF28-300mm is still a much loved and highly evaluated by photographers around the world as a representative model of high power zoom lenses.
With the market influx of digital SLR cameras in recent years, the use of high power zoom lenses has become increasingly popular since high power zooms provide the convenience of handling many photographic scenes and the capability of shooting ultra telephoto shots without changing lenses. The popularity of this focal length led Tamron to initiate the development of new zoom lenses to further meet the needs of digital SLR photographers. The result is the successful development of a new zoom lens exclusively for use on digital SLR cameras. The wide to ultra tele focal range of this lens will allow digital SLR camera owners to enjoy digital photography with comfort and convenience.
Dedicated for Digital SLR Cameras
By incorporating an optical design for exclusive use with digital (APS-C) SLR cameras, this high power zoom lens provides the focal length equivalent to Tamron's 28-300mm (when converted to a 35mm format). Therefore, you can meet almost all photographic opportunities with this single zoom lens without changing lenses. When paired with the SP AF11-18mm zoom lens, simultaneously introduced by Tamron at Photokina, you can enjoy thoroughly digital SLR photography with the combined focal length coverage of 17-300mm.
Optical System Uses Special Glass and is Optimized for Digital SLR Characteristics in order to Enhance Optical Quality in a Compact Design
The new AF18-200mm high power zoom lens from Tamron features an entirely new optical design using XR (Extra Refractive Index) glass in an innovative way in order to optimize the overall distribution of optical power throughout the entire zoom range. This design reduces various aberrations to the absolute minimum and achieves remarkable downsizing at the same time. In addition, three hybrid aspherical lens elements and two LD (Low Dispersion) glass elements are used to accomplish effective compensation of on-axis and lateral chromatic aberrations, a critical factor to enhance the optical quality in digital photography. As a result, the lens provides outstanding optical quality in a multi-purpose zoom lens.
Optical Design Dedicated to Digital SLR Photography by Optimizing the Angles of Incidences of Light Rays Reaching the Imager
The zoom lens uses a new optical system designed to confine the changing angles of incidences of light rays reaching the imager within a certain scope over the entire image field from the center to the periphery, by considering the effects of variances due to zooming.
Enhanced Peripheral Illumination
Peripheral light fall-off is minimized when compared with that of conventional lenses for film cameras so that images are uniformly bright from the center to the periphery.
Since the lens is designed exclusively for digital SLR photography, it provides high image quality in terms of resolution, contrast and flatness of image field.
Internal Surface Coating to Reduce Ghosting and Flare
Ghosting and flare caused by aberrations are annoying factors in digital SLR photography, so Tamron has adopted various countermeasures against the problem including the employment of "Internal Surface Coatings" (i.e., multiple-layer coatings on cemented surfaces of plural elements) and new multiple-layer coating technology on ordinary elements in order to minimize reflections that occur when light enters through the front element and to reduce image degrading effects caused by the imagers themselves.
Revolutionary MFD - 0.45m over the Entire Zoom Range for 1:3.7 Macro Capability
The new 18-200mm zoom lens realizes an MFD (Minimum Focus Distance) of 0.45m over the entire zoom range, which is better than that of the conventional 28-300mm zoom lens, by the employment of a new optical/mechanical design configuration. Since the maximum magnification ratio at f=200mm is 1:3.7, you can enjoy close-up photography easily and conveniently.
High Power, Yet Compact and Lightweight Thanks to New Mechanical Artifices
Complicated mechanisms are built in the compact body thanks to new mechanical artifices. The lens is a multi-purpose zoom lens, yet excellent portability and ease of use are assured. A number of invisible engineering innovations required to downsize the lens, produce high precision parts and increase durability are incorporated in the new AF18-200mm F/3.5-6.3 XR Di-II Aspherical (IF) MACRO since manufacturing this type of zoom lens with such complicated mechanisms inside was almost impossible with conventional manufacturing technology.
Zoom Lock Mechanism Incorporated
The Zoom Lock prevents unwanted barrel extension when carrying the lens/camera combination.
Flower-shaped Lens Hood
A glare-reducing flower-shaped lens hood is included as a standard accessory. The special hood provides optimum shading of superfluous light rays that enter from the rectangular frame outside the image field.
New External Design Conveys "High Performance, High Precision Image" as One of the New Di-II Series
Improvements have been made to the external design 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.
|Focal Length: ||18-200mm|
|Maximum Aperture: ||F/3.5-6.3|
|Minimum Aperture: ||F/22|
|Angle of View: ||75 degrees - 8 degrees|
|Lens Construction: ||15 elements / 13 groups|
|MFD (Minimum Focus Distance): |
|0.45m (17.7") (entire zoom range)|
|Diaphragm Blades: ||7|
|Filter Size: ||62mm|
|Size (Diameter x Length): ||2.9 in. x 3.3 in. (?73mm x 83.7mm)*|
|Weight: ||423g (14.9 oz.) (approx. design value)*|
|Max. Mag. Ratio: ||1:2.7|
|Standard Accessory: ||Flower-Shaped Hood|
* "Di (Digitally Integrated design)-II" is the designation Tamron puts on lenses designed for exclusive use with digital (APS-C size) SLR cameras, featuring optical systems optimized to meet the performance characteristics of digital cameras.
* "Di-II" lenses cannot be used with digital SLR cameras using image sensors that are larger than that of an APS-C size imager, or with 35mm film SLR cameras.