Pentax smc Pentax-M 20mm f/4 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-M 20mm f/4 if
- You want a compact lens: 29.5 mm vs 86.9 mm long
Pick the Samyang 20mm T1.9 ED AS UMC if
- You need 2 stops more light for low light or background blur (f/1.9 vs f/4)
- You shoot close-ups: it focuses down to 0.2 m vs 0.25 m
Spec differences
8 differences| Pentax smc Pentax-M 20mm f/4 | Samyang 20mm T1.9 ED AS UMC | |
|---|---|---|
| Brand |
Pentax
|
Samyang
|
| Max aperture |
f/4
|
f/1.9
2 stops faster
|
| Weight |
150 g
|
not listed
|
| Length |
29.5 mm
shorter
|
86.9 mm
|
| Diameter |
63 mm
slimmer
|
83 mm
|
| Filter thread |
49 mm
|
77 mm
|
| Min focus distance |
0.25 m
|
0.2 m
closer
|
| Optical design |
8 elements / 8 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-M 20mm f/4
Pentax smc Pentax-M 20mm f/4: a wide-angle prime lens with a 20mm focal length and a maximum aperture of f/4, made for Pentax K mount cameras. The wide view suits landscapes, architecture and environmental shots.
Our notes
Samyang 20mm T1.9 ED AS UMC
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