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Pentax smc Pentax-A 20mm f/2.8 vs Samyang 20mm T1.9 ED AS UMC

Both are Pentax K prime lenses for full frame. Here is what actually differs.

Pick the Pentax smc Pentax-A 20mm f/2.8 if

Our spec data shows no clear advantage for this lens.

Pick the Samyang 20mm T1.9 ED AS UMC if

  • You need 1 stop more light for low light or background blur (f/1.9 vs f/2.8)
  • You shoot close-ups: it focuses down to 0.2 m vs 0.25 m

Spec differences

7 differences
Specifications that differ between the Pentax smc Pentax-A 20mm f/2.8 and the Samyang 20mm T1.9 ED AS UMC
Pentax smc Pentax-A 20mm f/2.8 Samyang 20mm T1.9 ED AS UMC
Brand
Pentax
Samyang
Max aperture
f/2.8
f/1.9 1 stop faster
Length
not listed
86.9 mm
Diameter
not listed
83 mm
Filter thread
67 mm
77 mm
Min focus distance
0.25 m
0.2 m closer
Optical design
10 elements / 9 groups
13 elements / 12 groups
6 identical specs hidden: mount, type, format, focal length, autofocus motor, image stabilization. Show all
Mount
Pentax K both
Type
Prime both
Format
Full frame both
Focal length
20mm both
Autofocus motor
Manual focus both
Image stabilization
No both

Our notes

Pentax smc Pentax-A 20mm f/2.8

The Pentax smc Pentax-A 20mm f/2.8 is a wide-angle prime lens covering 20mm at f/2.8 for Pentax K mount cameras. The wide view suits landscapes, architecture and environmental shots.

Our notes

Samyang 20mm T1.9 ED AS UMC

More comparisons

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