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Buying Lenses Sigma 10-20mm f/4-5.6 EX DC HSM Lens for Nikon Digital SLR Cameras
Sigma 10-20mm f/4-5.6 EX DC HSM Lens for Nikon Digital SLR Cameras
From Sigma Corporation
From the Manufacturer
The 10 to 20 millimeters f4 to 5.6 EX DC HSM lens allows enjoyment of super wide-angle photography and it is a very powerful tool for indoor shooting and landscape photography with APS-C size image sensors of digital SLR cameras.
Wide angle of view (102.4 degrees at 10 millimeters and 63.8 degrees at 20 millimeters) offers the photographer greater freedom of expression.
Three SLD glass elements are employed for effective compensation of color aberration, which is a common problem with super-wide angle lenses. One piece of glass mold and two hybrid aspherical lenses, offer excellent correction for distortion, as well as all types of aberration.
This lens is equipped with an inner focusing system, and the models which are equipped with HSM system provide quiet, high speed autofocus shooting and also offer full time manual focusing. It has a minimum focusing distance of 24 centimeters (9.4 inches) at all focal lengths. The non-rotating lens barrel perfectly suits the petal shaped lens hood. A circular polarizing filter can also be used conveniently.
Sigma AF 18-200mm f/3.5-6.3 DC OS (Optical Stabilizer) Zoom Lens for Canon Digital SLR Cameras
Sigma AF 18-200mm f/3.5-6.3 DC OS (Optical Stabilizer) Zoom Lens for Canon Digital SLR Cameras
From SIGMA
List Price: $750.00
Price: $449.00 & eligible for FREE Super Saver Shipping on orders over $25. Details
The Sigma 18-200mm high-zoom-ratio lens is designed exclusively for Canon digital SLR cameras and is capable of covering a wide range of focal lengths, from wide-angle to telephoto. Two Special Low Dispersion (SLD) glass elements and two hybrid aspherical lenses correct for all types of aberrations, letting Sigma house the extended-range super-zoom lens in a compact and lightweight body that measures 70mm in diameter and 78.1mm long and weighs a mere 14.3 ounces. The new lens coating, meanwhile, reduces flare and ghost–a common problem shared by many digital cameras–while also creating an optimum color balance. Other details include a minimum focusing distance of 45cm (17.7) at all focal lengths, a high zoom ratio of 11:1, and a maximum magnification of 1:4.4.
The lens design incorporates an inner focusing system that prevents the front of the lens from rotating, making it particularly suitable for using circular polarizing filters and petal-shaped lens hoods. In addition, the overall length of the lens never changes during focusing, making the lens convenient to handle and easy to use. Finally, the lens’s zoom lock switch eliminates "zoom creep" during transport–a convenient addition when traveling. The lens, which includes a metal mount, is backed by a one-year warranty.
