Samyang 21mm f/1.4 ED AS UMC CS
Summary
The Samyang 21mm f/1.4 ED AS UMC CS is a solid optical performer — a wide-angle prime (32mm equivalent) with f/1.4 maximum aperture. The lens is priced at approximately ~$500 USD. Please check the official product page for sample images, manuals, and firmware updates.
Genre Suitability
- Excellent for: Landscape, Architecture, Street, Travel
- Adequate for: Nightscape, Portrait, Sport, Wildlife
- Avoid for: Macro
Strengths
- Good flare resistance
- Negligible distortion
Weaknesses
- Noticeably soft corners wide open
- Noticeable vignetting wide open
Specifications 19/20
| Optical construction | 8 elements in 7 groups (3 aspherical, 1 ED) |
| Coating | UMC |
| Focal length | 21mm |
| Max aperture | f/1.4 |
| Sweet spot | f/4 |
| Aperture blades | 7 |
| Sunstar points | 14 (sharp — straight blades) |
| Max magnification | 0.2x |
| Min focus distance | 280mm |
| AF motor | Manual focus |
| OIS | No |
| Weather sealed | No |
| Aperture ring | Yes |
| Clickless aperture | No |
| Focus ring | Yes |
| Focus by wire | No |
| Distance scale | Yes |
| Rotating front | No |
| Tripod mount | No |
| Weight | 300g |
| Diameter | 64.3mm |
| Length | 67.9mm |
| Filter thread | 58mm |
| Year | 2016 |
MTF Charts
| Position | 10S | 10M | 30S | 30M |
|---|---|---|---|---|
| Center | 0.98 | 0.99 | 0.89 | 0.88 |
| 2mm | 0.98 | 0.98 | 0.90 | 0.89 |
| 4mm | 0.98 | 0.98 | 0.91 | 0.89 |
| 6mm | 0.99 | 0.98 | 0.90 | 0.88 |
| 8mm | 0.99 | 0.98 | 0.89 | 0.86 |
| 10mm | 0.98 | 0.97 | 0.87 | 0.87 |
| 12mm | 0.98 | 0.97 | 0.86 | 0.86 |
| 14mm | 0.97 | 0.97 | 0.83 | 0.83 |
| Position | 10S | 10M | 30S | 30M |
|---|---|---|---|---|
| Center | 0.99 | 0.99 | 0.98 | 0.98 |
| 2mm | 0.99 | 0.99 | 0.98 | 0.97 |
| 4mm | 0.99 | 0.99 | 0.98 | 0.96 |
| 6mm | 0.99 | 0.99 | 0.98 | 0.95 |
| 8mm | 0.99 | 0.98 | 0.98 | 0.93 |
| 10mm | 0.99 | 0.98 | 0.98 | 0.90 |
| 12mm | 0.99 | 0.97 | 0.98 | 0.87 |
| 14mm | 0.99 | 0.97 | 0.98 | 0.87 |
Optical Quality 14/14
| Center (wide open) | 1.0 |
| Corner (wide open) | 0.5 |
| Center (stopped) | 2.0 |
| Corner (stopped) | 1.5 |
| Coma | 1.5 |
| Astigmatism | 1.0 |
| Spherical aberration | 2.0 |
| Longitudinal CA | 1.0 |
| Lateral CA | 1.5 |
| Distortion | 1.5 |
| Vignetting (wide open) | 0.5 |
| Vignetting (stopped) | 1.5 |
| Bokeh | 1.0 |
| Flare resistance | 2.0 |
Sharpness
- Acceptable center sharpness wide open
- Noticeably soft corners wide open
- Outstanding center resolution stopped down
- Good corner-to-corner sharpness stopped down
Aberrations
- Moderate longitudinal CA, correctable in post
- Well-controlled lateral CA
- Well-controlled coma
- Moderate astigmatism
- Excellent spherical aberration correction
Rendering
- Acceptable bokeh rendering
- Noticeable vignetting wide open
- Vignetting clears well when stopped down
- Excellent flare resistance — backlit scenes handled confidently
Distortion
- Minimal distortion
All optical scores are based on lab measurements and field tests from trusted review sources. For details on how we score lenses, see our scoring methodology.
Genre Fit
~ Nightscape Photography 3/5
Nightscape Photography prioritizes coma control, astigmatism correction, and a fast aperture for short star exposures.
- Well-controlled coma
- Moderate astigmatism
- Fast f/1.4 aperture
- Well-controlled lateral CA
- Acceptable center sharpness wide open
- Noticeably soft corners wide open
- Moderate longitudinal CA, correctable in post
- Noticeable vignetting wide open
- Excellent spherical aberration correction
✓ Landscape Photography 4/5
Landscape Photography prioritizes corner-to-corner sharpness at stopped-down apertures and good flare resistance.
- Good corner-to-corner sharpness stopped down
- Outstanding center resolution stopped down
- Minimal distortion
- Well-controlled lateral CA
- Moderate longitudinal CA, correctable in post
- Vignetting clears well when stopped down
- Excellent flare resistance — backlit scenes handled confidently
- Moderate astigmatism
- Well-controlled coma
✓ Architecture Photography 4/5
Architecture Photography prioritizes geometric precision with minimal distortion and even corner sharpness.
- Good corner-to-corner sharpness stopped down
- Outstanding center resolution stopped down
- Minimal distortion
- Well-controlled lateral CA
- Vignetting clears well when stopped down
- Excellent flare resistance — backlit scenes handled confidently
✓ Street Photography 4.5/5
Street Photography prioritizes sharp stopped-down performance and a fast enough aperture for low light.
- Outstanding center resolution stopped down
- Fast f/1.4 aperture
- Acceptable center sharpness wide open
- Excellent flare resistance — backlit scenes handled confidently
- Moderate longitudinal CA, correctable in post
- Well-controlled coma
✓ Travel Photography 4/5
Travel Photography prioritizes balanced image quality in a lightweight package.
- Outstanding center resolution stopped down
- Lightweight at 300g
- Fast f/1.4 aperture
- Excellent flare resistance — backlit scenes handled confidently
- Moderate longitudinal CA, correctable in post
~ Portrait Photography 3/5
Portrait Photography prioritizes smooth bokeh and critical center sharpness wide open for subject isolation.
- Acceptable bokeh rendering
- Acceptable center sharpness wide open
- Moderate longitudinal CA, correctable in post
- Excellent spherical aberration correction
- Noticeable vignetting wide open
~ Sport Photography 3/5
Sport Photography prioritizes sharp wide-open center performance to freeze action at fast shutter speeds.
- Acceptable center sharpness wide open
- Fast f/1.4 aperture
- Moderate longitudinal CA, correctable in post
- Well-controlled lateral CA
~ Wildlife Photography 3/5
Wildlife Photography prioritizes center sharpness across apertures for distant subjects.
- Acceptable center sharpness wide open
- Outstanding center resolution stopped down
- Fast f/1.4 aperture
- Moderate longitudinal CA, correctable in post
- Well-controlled lateral CA
✗ Macro Photography 2/5
Macro Photography prioritizes stopped-down center sharpness and high magnification for close-up detail.
- Outstanding center resolution stopped down
- Low magnification (0.2x)
- Minimal distortion
- Well-controlled lateral CA
- Moderate longitudinal CA, correctable in post
- Excellent spherical aberration correction
- Acceptable bokeh rendering