Quick answer
The Sigma 17-50mm f/2.8 EX DC OS HSM is a ultra-wide to standard zoom lens covering 17-50mm at f/2.8 for the Pentax K mount. Its bright maximum aperture handles indoor and evening light reasonably well.
About this lens
Sigma 17-50mm f/2.8 EX DC OS HSM: an APS-C fast standard zoom lens with a 17-50mm focal length and a maximum aperture of f/2.8, made for Pentax K mount cameras, with Optical Stabilizer and Hyper Sonic Motor autofocus. A bright standard zoom for APS-C cameras with a constant f/2.8 aperture.
Sigma 17-50mm f/2.8 EX DC OS HSM specifications
- Brand
- Sigma
- Mount
- Pentax K
- Focal length
- 17-50mm
- Maximum aperture
- f/2.8
- Lens type
- Zoom
- Format coverage
- aps-c
- Optical construction
- 17 elements in 13 groups
- Aperture blades
- 7
- Image stabilization
- Yes
- Autofocus motor
- HSM
- Minimum focus distance
- 0.28 m
- Maximum magnification
- 0.2x
- Filter thread
- 77 mm
- Weight
- 565 g
- Length
- 91.8 mm
- Diameter
- 83.5 mm
Specification source: sigmaphoto.com
What can you shoot with the Sigma 17-50mm f/2.8 EX DC OS HSM?
At 17-50mm this is a ultra-wide to standard zoom, which typically suits:
- Landscapes and big skies
- Architecture and interiors
- Astrophotography and night skies
- Landscapes and cityscapes
- Street and travel photography
Its bright maximum aperture handles indoor and evening light reasonably well.
Full-frame equivalent and field of view
Calculated from the focal length and crop factor. Not measured.
| Sensor | Crop | Equivalent | Horizontal FOV | Diagonal FOV |
|---|---|---|---|---|
| APS-C | 1.5x | 26–75mm | 27–70.4° | 32.2–80.6° |
Frequently asked questions
What mount does the Sigma 17-50mm f/2.8 EX DC OS HSM use?
It uses the Pentax K mount, so it fits Pentax K cameras directly.
What is the focal length of the Sigma 17-50mm f/2.8 EX DC OS HSM?
It zooms across 17-50mm with a maximum aperture of f/2.8. That makes it a ultra-wide to standard lens.
Is the Sigma 17-50mm f/2.8 EX DC OS HSM a prime or a zoom lens?
It is a zoom lens covering 17-50mm, so you can reframe without moving. Its maximum aperture is f/2.8.
What is the Sigma 17-50mm f/2.8 EX DC OS HSM equivalent on a crop sensor?
On APS-C (1.5x crop) it frames like 26–75mm on full frame, with a 27–70.4° horizontal and 32.2–80.6° diagonal field of view. These figures are calculated from the focal length and crop factor.
Which cameras does the Sigma 17-50mm f/2.8 EX DC OS HSM fit?
Any Pentax K-mount camera, including Pentax K-1, Pentax K-3, Pentax K-3 II, Pentax K-3 Mark III, and Pentax K-30 and 15 more.
Alternatives for Pentax K from other brands
All Pentax K lensesSame mount, overlapping focal range, closest maximum aperture first.
More Sigma lenses for Pentax K
All Sigma lenses
Other 17-50mm lenses
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