Sigma 10-20mm F3.5 EX DC HSM is an Auto Focus (AF) Wideangle Zoom
lens with APS-C / DX max sensor coverage and it is designed to be used with Pentax KAF3 mount cameras.
Sigma 10-20mm F3.5 EX DC HSM is compatible with cameras that have Pentax KAF3 lens mount.Some of the latest released cameras with Pentax KAF3 lens mount are
Max sensor coverage of Sigma 10-20mm F3.5 EX DC HSM is APS-C / DX.
Sigma 10-20mm F3.5 EX DC HSM has a focal range of 10-20mm and 2.0X zoom ratio.
Optical Image Stabilization
Sigma 10-20mm F3.5 EX DC HSM doesn't have an optical image stabilization system so the only option to stabilize the image taken with this lens is to mount on a camera body with IBIS (sensor based In-body image stabilization).
Sigma 10-20mm F3.5 EX DC HSM features Rotary (extending) zoom method where the length of the lens changes as you zoom in or out. This makes it possible to design the lens with a smaller minimum length ( generally when it is zoomed out) compared to internal zoom lenses. The disadvantages of this design are being harder to seal against dust and moisture, weight balance shifting while zooming and zoom creep in certain lenses.
Sigma 10-20mm F3.5 EX DC HSM is a fixed aperture lens with a constant max aperture of f3.5 from 10mm all the way to the 20mm .
Sigma 10-20mm F3.5 EX DC HSM's optical formula consists of 13 elements in 10 groups.