Samyang Pentax K mount Ultra-wide prime
Samyang 20mm T1.9 ED AS UMC
Quick answer
The Samyang 20mm T1.9 ED AS UMC is a ultra-wide prime lens covering 20mm at f/1.9 for the Pentax K mount. Its fast maximum aperture helps in dim light and gives good subject separation.
- Full frame
- APS-C (30mm equiv.)
- 29 Pentax K cameras
- Focal
- 20mm
- Aperture
- f/1.9
- Filter
- 77mm
- Min focus
- 0.2m
- AF motor
- None
What 20mm sees
- Full frame crop 1.0×
- 94.5° 84° horizontal
- APS-C crop 1.5× → 30mm
- 71.6° 61.9° horizontal
Diagonal angle of view. Frames drawn to scale at 20mm. Calculated from the focal length and crop factor, not measured.
Open the field-of-view calculatorSamyang 20mm T1.9 ED AS UMC specifications
Optics
- Focal length
- 20mm
- Maximum aperture
- f/1.9
- Format coverage
- Full frame
- Optical construction
- 13 elements in 12 groups
Focus
- Autofocus motor
- None
- Minimum focus distance
- 0.2 m
Physical
- Filter thread
- 77 mm
- Length
- 86.9 mm
- Diameter
- 83 mm
Specification source: lksamyang.com
What can you shoot with the Samyang 20mm T1.9 ED AS UMC?
At 20mm this is a ultra-wide prime, which typically suits:
- Landscapes and big skies
- Architecture and interiors
- Astrophotography and night skies
Its fast maximum aperture helps in dim light and gives good subject separation.
Frequently asked questions
What mount does the Samyang 20mm T1.9 ED AS UMC use?
It uses the Pentax K mount, so it fits Pentax K cameras directly.
What is the focal length of the Samyang 20mm T1.9 ED AS UMC?
It is a fixed 20mm lens with a maximum aperture of f/1.9. That makes it a ultra-wide lens.
Is the Samyang 20mm T1.9 ED AS UMC a prime or a zoom lens?
It is a prime lens with a fixed 20mm focal length. Primes usually open wider than zooms; this one opens to f/1.9.
What is the Samyang 20mm T1.9 ED AS UMC equivalent on a crop sensor?
On APS-C (1.5x crop) it frames like 30mm on full frame, with a 61.9° horizontal and 71.6° diagonal field of view. These figures are calculated from the focal length and crop factor.
Which cameras does the Samyang 20mm T1.9 ED AS UMC 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.
