Sigma 17-50mm F2.8 EX DC OS HSM is a Fixed aperture Auto Focus (AF)
Standard Zoom lens with Optical Image stabilization and APS-C / DX max sensor coverage, and it is designed to be used with
KAF3 Mount cameras.
What type of photography is the Sigma 17-50mm F2.8 EX DC OS HSM lens good for?
The type of photography that you are planning to use the Sigma 17-50mm F2.8 EX DC OS HSM is an important decision factor. Here we have evaluated its suitability to various photography scenarios:
Reasons to Buy Sigma 17-50mm F2.8 EX DC OS HSM Lens
Here we've included a summary of the advantages and disadvantages of the Sigma 17-50mm F2.8 EX DC OS HSM lens in a list form to help you determine whether it offers the features you need.
Optical Image Stabilization |
Autofocus |
Distance Scale |
Hood supplied |
Fast Aperture at Wide end |
Fast Aperture at Tele end |
Constant f2.8 aperture throughout the range |
Minimum focus distance of 0.28m / 11.0 inch |
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No Weather Sealing |
Lens Extends while zooming |
Lens Mount
Sigma 17-50mm F2.8 EX DC OS HSM is compatible with cameras that have a Pentax KAF3 lens mount. Some of the latest released cameras that are compatible with the Pentax KAF3 lenses are , and .
Sigma 17-50mm F2.8 EX DC OS HSM is also available in Canon EF , Sony Alpha, Sigma SA and Nikon F (DX) mounts.
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Size, Weight and Filter Thread
Size and weight is a very important decision factor when searching for your next lens. Sigma 17-50mm F2.8 EX DC OS HSM has a maximum diameter of 84mm and total length of 92mm when not extended. It weighs 565g / 19.9 oz.
Sigma 17-50mm F2.8 EX DC OS HSM has a filter thread of 77mm. Below are links to the filters that we recommend you to consider for your Sigma 17-50mm F2.8 EX DC OS HSM:
Focal Range
Sigma 17-50mm F2.8 EX DC OS HSM has a focal range of 17-50mm and 2.9X zoom ratio which has a 35mm equivalent focal range of 25.5-75mm when used on a APS-C / DX format camera.
Optical Image Stabilization
The Sigma 17-50mm F2.8 EX DC OS HSM features an optical image stabilization system which helps to reduce the blur that occurs due to shaking during hand-held shooting.
Zoom Method
Sigma 17-50mm F2.8 EX DC OS 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.
Maximum Magnification Ratio
Sigma 17-50mm F2.8 EX DC OS HSM has a Max Magnification Ratio of 0.2x and has a minimum focusing distance of 0.28m.
Below are the 3 Standard Zoom type Pentax KAF3 mount lens alternatives with highest max magnification ratios:
Aperture
Sigma 17-50mm F2.8 EX DC OS HSM is a fixed aperture lens with a constant max aperture of f2.8 from 17mm all the way to the 50mm .
Focal Length |
Max Aperture |
Min Aperture |
17mm
|
F2.8 |
F22 |
50mm
|
F2.8 |
F22 |
Optical Formula
Sigma 17-50mm F2.8 EX DC OS HSM's optical formula consists of 17 elements in 13 groups . Following special elements are used in this design:
- 2 FLD glass elements
- 2 glass mold elements
- 1 hybrid aspherical lens
Lens Hood
Sigma 17-50mm F2.8 EX DC OS HSM comes with a removable lens hood which is handy to reduce lens flare and glare in your photos.
Popular Comparisons of Sigma 17-50mm F2.8 EX DC OS HSM
Here are the eight most popular comparisons of the Sigma 17-50mm F2.8 EX DC OS HSM amongst Camera Decision readers.
Top Alternatives of Sigma 17-50mm F2.8 EX DC OS HSM Lens
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