Sigma Pentax K mount Superzoom
Sigma 18-125mm f/3.8-5.6 DC OS HSM
Quick answer
The Sigma 18-125mm f/3.8-5.6 DC OS HSM is a ultra-wide to short telephoto superzoom lens covering 18-125mm at f/3.8 for the Pentax K mount. Its moderate maximum aperture works best in good light or with a higher ISO.
- APS-C (27–188mm equiv.)
- 29 Pentax K cameras
- Focal
- 18–125mm
- Aperture
- f/3.8–22
- Filter
- 67mm
- Min focus
- 0.35m
- AF motor
- HSM
What 18-125mm sees
- APS-C crop 1.5× → 27–188mm
- 13.2–77.4° 11–67.4° horizontal
Diagonal angle of view. Frames drawn to scale at 18mm. Calculated from the focal length and crop factor, not measured.
Open the field-of-view calculatorSigma 18-125mm f/3.8-5.6 DC OS HSM specifications
Optics
- Focal length
- 18-125mm
- Maximum aperture
- f/3.8
- Minimum aperture
- f/22
- Format coverage
- APS-C
- Optical construction
- 16 elements in 12 groups
- Aperture blades
- 7
- Image stabilization
- Yes
Focus
- Autofocus motor
- HSM
- Minimum focus distance
- 0.35 m
- Maximum magnification
- 0.26×
Physical
- Filter thread
- 67 mm
Specification source: sigma-global.com
What can you shoot with the Sigma 18-125mm f/3.8-5.6 DC OS HSM?
At 18-125mm this is a ultra-wide to short telephoto superzoom, which typically suits:
- Landscapes and big skies
- Architecture and interiors
- Astrophotography and night skies
- Landscapes and cityscapes
- Street and travel photography
Its moderate maximum aperture works best in good light or with a higher ISO.
Frequently asked questions
What mount does the Sigma 18-125mm f/3.8-5.6 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 18-125mm f/3.8-5.6 DC OS HSM?
It zooms across 18-125mm with a maximum aperture of f/3.8. That makes it a ultra-wide to short telephoto lens.
Is the Sigma 18-125mm f/3.8-5.6 DC OS HSM a prime or a zoom lens?
It is a zoom lens covering 18-125mm, so you can reframe without moving. Its maximum aperture is f/3.8.
What is the Sigma 18-125mm f/3.8-5.6 DC OS HSM equivalent on a crop sensor?
On APS-C (1.5x crop) it frames like 27–188mm on full frame, with a 11–67.4° horizontal and 13.2–77.4° diagonal field of view. These figures are calculated from the focal length and crop factor.
Which cameras does the Sigma 18-125mm f/3.8-5.6 DC OS HSM fit?
Any Pentax K-mount camera, including Pentax *ist DL, Pentax *ist DS, Pentax K-01, Pentax K-1, and Pentax K-3 and 24 more.
Alternatives for Pentax K from other brands
All Pentax K lensesSame mount, overlapping focal range, closest maximum aperture first.
![Pentax smc Pentax-FA 28-200mm f/3.8-5.6 AL [IF]](https://upload.wikimedia.org/wikipedia/commons/thumb/2/2f/SMC_Pentax-FA_3.8-5.6-28-200_mm.jpg/500px-SMC_Pentax-FA_3.8-5.6-28-200_mm.jpg)
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