Sigma's 17-50 mm F2.8 EX DC OS large aperture standard zoom lens covers a focal length from 17 mm wide angle & offers a large aperture of F2.8 throughout the entire zoom range, making it ideal for many types of photography especially portraiture & landscapes. The OS, Sigma's anti shake feature offers the use of shutter speeds Approx. 4 stops slower than would otherwise be possible. Sigma's own FLD glass elements, which have performance equal to fluorite along with two glass mold & one hybrid aspherical lens, provide excellent correction for all types of aberrations. The super multi layer coating reduces flare & ghosting. This lens boasts superior peripheral brightness & provides sharp, high contrast images even at the maximum apertures. With a minimum focusing distance throughout the entire zoom range & a magnification ratio. When you need to stand ready for any photo opportunity you need a fast aperture so you can shoot in low existing light or at maximum range with a flash. This Sigma lens is perfect. With its compact size & light weight, it's a necessary addition to your camera bag. ...

To achieve an F2.8 aperture at all focal lengths, it employs three aspherical lens to provide optimum aberration compensation. Two Special Low Dispersion (SLD) glass elements are provided for color aberration compensation, to assure high image quality. ...

As a member of the EX series of lenses this third generation Sigma lens is designed with the highest level of optical technology & augments its predecessor with the addition of the Hyper-Sonic Motor (HSM) ensuring a quiet, high speed AF as well as full-time manual focusing capability. Housed in compact construction, the Sigma 24-70mm is a large aperture standard zoom lens ideal for all general photography including portraiture & landscapes. Physically, the shortest lens in the category, its overall length is 3.7 inches/94.7mm. With excellent optics, this could be the foremost performing lens in the category with stunning speed, clarity & color. Intricate lens construction

Includes:: Super Multi Layer Coating reducing flare & ghosting; the combination of ELD (Extraordinary Low Dispersion) & two SLD (Special Low Dispersion) glass elements & three aspherical lenses provide excellent correction of all types of aberrations. Superior optical performance is ensured throughout the entire zoom range with the minimum focusing distance being 15in/38cm & maximum magnification ratio being 1:5.3. The rounded 9 blade diaphragm gives a natural look to backgrounds & foregrounds.

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To achieve an F2.8 aperture at all focal lengths, it employs three aspherical lens to provide optimum aberration compensation. Two Special Low Dispersion (SLD) glass elements are provided for color aberration compensation, to assure high image quality. ...

The Sigma 120-300 m F2.8 EX DG OS APO HSM is a unique lens in the photo industry. Its design is based around high speed superior optical performance. Created for full frame sensors, it may also be used with APS-C sized sensors as well. It has an array of technology to guarantee the highest level of image quality. This technology

Includes:: a Hyper Sonic Motor (HSM), an Optical Stabilizer, Inner Focusing & Zooming System, SLD & FLD Glass Elements (FLD has a performance equal to fluorite). The HSM ensures quiet, high speed, accurate autofocusing while the OS allows for use of shutter speeds Approx. 4 stops slower than would otherwise be possible. Super Multi-Layer coating reduces flare & ghosting working together with the SLD & FLD glass elements for maximum correction of chromatic aberrations. An inner focusing & zooming system produces sharper images throughout the entire zoom range.

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This telephoto zoom lens incorporates Sigmas original OS (Optical Stabilizer) function. Three SLD (Special Low Dispersion) glass elements provide excellent correction for chromatic aberration. This lens is equipped with the rear focus system that minimizes fluctuation of aberration caused by focusing. It provides optimum image quality throughout the entire zoom range. The super multi-layer coating reduces flare & ghosting. High image quality is assured throughout the entire zoom range. ...

This telephoto zoom lens incorporates Sigmas original OS (Optical Stabilizer) function. Three SLD (Special Low Dispersion) glass elements provide excellent correction for chromatic aberration. This lens is equipped with the rear focus system that minimizes fluctuation of aberration caused by focusing. It provides optimum image quality throughout the entire zoom range. The super multi-layer coating reduces flare & ghosting. High image quality is assured throughout the entire zoom range. ...

This product is an ultra-telephoto zoom lens covering a telephoto range up to 500 mm, incorporating Sigma's original OS (Optical Stabilizer) function. This function uses two sensors inside the lens to detect vertical & horizontal movement of the camera & works by moving an optical image stabilizer lens group to effectively compensate for camera shake. It offers the use of shutter speeds Approx. 4 stops slower. Mode 1 is ideal for general photography, & Mode 2 is effective on moving subject such as motor sports & so on. ...

This ultra telephoto zoom lens covers a telephoto range up to 500 mm & allows photographers to bring the subject close with short perspective. Sigma's original OS function offers the equivalent of using a shutter speed Approx. 4 stops faster. It is ideal for sports, wildlife & landscape photography with handheld shooting. ...

Sigmas proprietary OS (Optical Stabilizer) system offers the use of shutter speeds Approx. 4 stops slower than would otherwise be possible, enabling hand held tele-photography. Six SLD glass elements compensate for chromatic aberrations & provide high image quality throughout the zoom range. The super multi-layer coating reduces flare & ghosting & ensures sharp & high contrast images even at the maximum apertures. The lens design adopts an inner focusing & inner zooming system to provide convenient handling & the HSM (Hyper Sonic Motor) ensures quiet & high speed autofocus while allowing full-time manual focus override. This lens has a minimum focusing distance of 80 cm (31.5") & a maximum magnification ratio of 1:6.3. The rounded 9 blade diaphragm creates an attractive blur to the out of focus areas of the image. ...