Sigma AF 10-20mm f/4-5.6 EX DC Wide Angle Zoom Lens for Pentax
This ultra-wide zoom lens has a wide angle of view from 102.4 - 63.8 degrees (when Sigma mount is used) and it is exclusive to digital SLR cameras. SLD glass elements effectively compensate color aberration. Aspherical lenses provide maximum correction for distortion and various aberrations; high image quality is displayed throughout the entire zoom range. The HSM equipped models makes fast AF speeds and quiet shooting a reality, and it is also capable of full-time manual focus. It has a minimum focusing distance of 9.4" (24cm) at all focal lengths. It is also equipped with an integral Petal-type hood to block out extraneous light.
Ultra-wide zoom lens
10-20mm F4-5.6 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 102.4-63.8 degrees (for Sigma mount) offers the photographer greater freedom of expression.
Most Appropriate Coating for Digital SLR Cameras
The new multi layer lens coating and lens design reduce flare and ghost, which is a common problem with digital cameras and also creates an optimum color balance through the entire zoom range.
The best possible correction of aberrations
Three SLD (Special Low Dispersion) 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.
Inner focus system
This lens incorporates an internal focusing system, which eliminates front lens rotation allowing the use of a Petal-type Hood and also minimize fluctuation of aberration caused by focusing system.
Minimum focusing distance of 9.4" (24cm) at all focal lengths
This lens has a minimum focusing distance of 9.4" (24cm) throughout the entire zoom range.
Key Features
- ASP (Aspherical Lens) - The aspherical lens complex allows freedom of design, improved performance, a reduced number of component lenses and a compact size.
- IF (Inner Focus) - To ensure stability in focusing, this lens moves the inner lens group or groups without changing the lens' physical length.
- EX (EX Lens) - The exterior of this lens is EX-finished to denote the superior build and optical quality, and to enhance its appearance.
- DC (DC Lens) - These are special lenses designed so that the image circle matches the smaller size of the image sensor of most digital SLR cameras. Their specialized design gives these lenses the ideal properties for digital cameras, the compact and lightweight construction is an added bonus ! including compact and lightweight construction.
Sample Image

By Stephen Lang