Rokinon 21mm F 1 4 ED AS UMC CS Review | 54 Data compared

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  • Avg. price in UK: ~£310
  • Avg. price in US: ~$330
  • Lens mount: Canon EF-M, Fujifilm X, Sony E, Micro Four Thirds
  • Maximum focal length: 21 mm
  • Maximum aperture (telephoto end): 1.4
  • Optical image stabilization: no
  • Maximum angle of view: 69.3 °

Rokinon 21mm F 1 4 ED AS UMC CS review. Compare 54 technical specifications and user reviews to see how it ranks among camera lenses and if it is worth buying.

6.9

Overall score

What it is: An overall evaluation of the camera lens's quality, based on technical analyses and user reviews.

When it matters: When you need a quick reference to identify the best camera lenses on the market.

Score components:

80.0%

6.9

Technical Score

20.0%

7.0

User score

Good
6.9

Technical Score

What it is: An assessment of the camera lens's technical performance, covering eight key areas: sharpness, aperture flexibility, autofocus, stabilization, build quality, mount compatibility, close-focus performance, and design.

When it matters: When you want to compare camera lenses based on technical performance and available features.

Score components:

35.0%

8.4

Optics & Aperture

24.0%

6.4

Build & Handling

20.0%

6.0

Focus & Controls

10.0%

9.0

Lab Scores

8.0%

4.2

Stabilization

3.0%

1.0

Mount & Format

Good
7.0

User score

What it is: A rating that combines user reviews and the total number of reviews received by the camera lens.

When it matters: When real-world owner satisfaction and review volume matter to your decision.

Score components:

70.0%

8.2

User reviews

30.0%

4.2

Popularity

User score:
United Kingdom
amazon
3.9
(56)
amazon
5.0
(3)
United States
Amazon_logo.png
4.0
(57)
Amazon_logo.png
4.3
(7)

(Reviews last updated: July 2026)

Very good
  • 7.3
    Low-light photography

    Score components:

    70.0%

    10

    Maximum aperture (telephoto end)

    30.0%

    1.0

    Optical image stabilization

  • 5.0
    Travel

    Score components:

    30.0%

    ?

    Lens length

    25.0%

    8.6

    Lens diameter

    25.0%

    1.0

    Weather sealing (splashproof)

    20.0%

    1.0

    Optical image stabilization

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Best prices in UK

Best rankings

?

Available: ranking among products currently available (including other versions of this product).
All: ranking among all products in the database.

Verdict

The Rokinon 21mm f/1.4 ED AS UMC CS is a fast, manual-focus wide-angle prime lens designed for mirrorless APS-C and Micro Four Thirds systems, featuring an optical construction of 8 elements in 7 groups including three aspherical lenses and one extra-low dispersion (ED) element. Its bright f/1.4 maximum aperture and 9-blade rounded diaphragm deliver exceptional low-light performance and smooth bokeh, while the Ultra Multi-Coating (UMC) effectively suppresses flare and ghosting. Key pros include high resolution and contrast even wide open, a compact and lightweight build (approx. 290g), a close 0.28m minimum focusing distance, and robust mechanical construction with a smooth, damped focus ring. Notable cons include the lack of autofocus and electronic coupling for EXIF data transmission, the absence of a hyperfocal scale on the barrel, and some noticeable purple fringing and corner softness when shooting at the maximum f/1.4 aperture.

Technical Specifications of Rokinon 21mm F 1 4 ED AS UMC CS

Technical Score

What it is: An assessment of the camera lens's technical performance, covering eight key areas: sharpness, aperture flexibility, autofocus, stabilization, build quality, mount compatibility, close-focus performance, and design.

When it matters: When you want to compare camera lenses based on technical performance and available features.

Score components:

35.0%

8.4

Optics & Aperture

24.0%

6.4

Build & Handling

20.0%

6.0

Focus & Controls

10.0%

9.0

Lab Scores

8.0%

4.2

Stabilization

3.0%

1.0

Mount & Format

6.9
Rokinon 21mm F 1 4 ED AS UMC CS has a technical score of 6.93 points, which is lower than 60.5% of camera lenses.
User score

What it is: A rating that combines user reviews and the total number of reviews received by the camera lens.

When it matters: When real-world owner satisfaction and review volume matter to your decision.

Score components:

70.0%

8.2

User reviews

30.0%

4.2

Popularity

User score:
United Kingdom
amazon
3.9
(56)
amazon
5.0
(3)
United States
Amazon_logo.png
4.0
(57)
Amazon_logo.png
4.3
(7)

(Reviews last updated: July 2026)

7.0
Rokinon 21mm F 1 4 ED AS UMC CS has a user score of 6.98 points, which is lower than 87.1% of camera lenses.
Popularity
What it is: An indicator based on the number of reviews received by the camera lens.
When it matters: When you want to see which camera lenses attract the most buyer attention and review activity.
4.2
Rokinon 21mm F 1 4 ED AS UMC CS has a popularity of 4.2 points, which is lower than 63.4% of products in this category.
Ratio quality/price

What it is: An indicator that combines the camera lens's overall rating with its cost.

When it matters: When you want to know how much overall quality you get for the price.

Score components:

60.0%

6.9

Overall score

40.0%

8.9

Price

7.5
Rokinon 21mm F 1 4 ED AS UMC CS has a quality-to-price ratio of 7.5 points, which is higher than 58% of products in this category.
Lens type
What it is: The optical category that indicates whether the lens is a prime, zoom, macro, fisheye, or another design.
When it matters: When you are choosing between a prime, zoom, macro, or specialty lens for the kind of subjects you shoot.

Importance: LOW

prime
Lens mount
What it is: The mechanical and electronic interface that determines which cameras the lens can be attached to.
When it matters: When camera compatibility and access to the right lens ecosystem are central to your buying decision.

Importance: LOW

Canon EF-M, Fujifilm X, Sony E, Micro Four Thirds
Sensor format coverage
What it is: The largest sensor size the lens is designed to cover without severe vignetting.
When it matters: When you need the lens to fully cover your camera sensor without heavy corner darkening.

Importance: LOW

APS-C
Filter thread size
What it is: The diameter of the front filter thread used for screw-in filters and compatible accessories.
When it matters: When you plan to use screw-in filters such as polarizers, ND filters, or protective glass.

Importance: LOW

58 mm
Teleconverter compatibility
What it is: Whether the lens can be used with compatible teleconverters to extend focal length.
When it matters: When you want to extend reach for wildlife or sports without changing to a different long lens.

Importance: HIGH

no
Rokinon 21mm F 1 4 ED AS UMC CS does not support teleconverters. 15.3% of camera lenses support teleconverters.
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Minimum focal length
What it is: The shortest focal length the lens can provide, which determines its widest framing.
When it matters: When wide framing matters for landscapes, interiors, architecture, or travel shots.

Importance: LOW

21 mm
Maximum focal length
What it is: The longest focal length the lens can reach, which determines its telephoto reach.
When it matters: When you need more reach for wildlife, sports, stage events, or distant details.

Importance: LOW

21 mm
Optical zoom
What it is: The ratio between the longest and shortest focal lengths available in the lens zoom range.
When it matters: When you want one lens to cover a broader range of compositions without swapping glass.

Importance: LOW

?
Maximum angle of view
What it is: The widest scene the lens can capture at its shortest focal length.
When it matters: When you need to fit more of a room, skyline, or landscape into the frame.

Importance: LOW

69.3 °
Minimum angle of view
What it is: The narrowest scene the lens captures at its longest focal length.
When it matters: When you want tighter framing on faraway subjects without moving closer.

Importance: LOW

66.4 °
Show more
Focus motor
What it is: The autofocus drive system responsible for moving lens elements into focus.
When it matters: When fast, quiet autofocus matters for video, wildlife, street shots, or moving subjects.

Importance: LOW

N/A
Minimum focus distance
What it is: The shortest distance at which the lens can focus on a subject.
When it matters: When you like shooting details, food, flowers, or products from a very short distance.

Importance: MEDIUM

0.28 m
Rokinon 21mm F 1 4 ED AS UMC CS focuses as close as 0.28 m, which is closer than 57.1% of camera lenses and equal to 6.6% of camera lenses.
Maximum reproduction ratio
What it is: The highest magnification the lens can achieve when focusing at its closest distance.
When it matters: When close-up magnification matters for macro work, textures, or small product details.

Importance: MEDIUM

0.2x
Rokinon 21mm F 1 4 ED AS UMC CS reaches a reproduction ratio of 0.2x, which is higher than 50.8% of camera lenses and equal to 7% of camera lenses.
Full-time manual focus
What it is: The ability to adjust focus manually without leaving autofocus mode.
When it matters: When you want to fine-tune focus instantly without switching out of autofocus.

Importance: HIGH

no
Rokinon 21mm F 1 4 ED AS UMC CS does not support full-time manual focus. 68.4% of camera lenses support full-time manual focus.
Internal focusing
What it is: A focusing design in which internal elements move while the outer barrel length stays unchanged.
When it matters: When you use polarizers, gimbals, or close-up setups that benefit from a lens that does not extend while focusing.

Importance: HIGH

yes
Rokinon 21mm F 1 4 ED AS UMC CS supports internal focusing. 83.6% of camera lenses support internal focusing.
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Optical image stabilization
What it is: A hardware system that shifts optical elements to counteract camera shake and reduce blur.
When it matters: When you want steadier handheld shots and less blur, especially in low light or at longer focal lengths.

Importance: HIGH

no
Rokinon 21mm F 1 4 ED AS UMC CS does not support optical image stabilization. 29% of camera lenses include optical image stabilization.
Stabilization effectiveness (CIPA stops)
What it is: The rated stabilizer benefit, measured in stops, under CIPA testing standards.
When it matters: When you are comparing stabilized lenses and want to know how much handheld shutter-speed advantage they offer.

Importance: HIGH

?
Weight
What it is: The total mass of the lens, affecting portability and handling balance on the camera body.
When it matters: When you carry a lens all day for travel, hiking, or event coverage and want to keep your kit manageable.

Importance: HIGH

?
Lens length
What it is: The physical length of the lens body from mount to front edge.
When it matters: When bag space, balance, or front clearance matters in a compact travel or video setup.

Importance: HIGH

?
Lens diameter
What it is: The widest outer diameter of the lens barrel.
When it matters: When grip comfort, filter size, or fit inside a tight camera bag matters to you.

Importance: MEDIUM

64.3 mm
Rokinon 21mm F 1 4 ED AS UMC CS has a diameter of 64.3 mm, which is slimmer than 84.4% of camera lenses and equal to that of 0.1% of camera lenses.
Weather sealing (splashproof)
What it is: Protective sealing intended to resist splashes, dust, and light environmental exposure.
When it matters: When you often shoot outdoors in light rain, dust, or changing conditions.

Importance: HIGH

no
Rokinon 21mm F 1 4 ED AS UMC CS does not support weather sealing. 50.3% of camera lenses support weather sealing.
Metal mount
What it is: A lens mount made of metal rather than plastic for greater durability at the camera connection point.
When it matters: When durability matters because you change lenses often or use heavier gear for work.

Importance: HIGH

yes
Rokinon 21mm F 1 4 ED AS UMC CS uses a metal lens mount. 93.1% of camera lenses use a metal lens mount.
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DxOMark overall score
What it is: The combined DxOMark lens rating based on lab-tested optical performance.
When it matters: When you want a quick lab-based summary of overall optical performance before comparing lenses in detail.

Importance: HIGH

?
DxOMark sharpness score
What it is: The DxOMark subscore that reflects how much detail the lens can resolve across the frame.
When it matters: When fine detail matters for landscapes, product work, or high-resolution cameras.

Importance: HIGH

?
DxOMark transmission
What it is: The measured light transmission of the lens, expressed as T-stop rather than nominal f-number.
When it matters: When real light loss matters for exposure consistency in studio, cinema, or mixed-lens shoots.

Importance: MEDIUM

?
DxOMark distortion
What it is: The DxOMark metric that measures how much the lens bends straight lines away from their true shape.
When it matters: When straight lines matter in architecture, interiors, copy work, or product photography.

Importance: MEDIUM

?
DxOMark vignetting
What it is: The DxOMark measurement of corner darkening relative to the center of the image.
When it matters: When even corner brightness matters for skies, studio backdrops, or clean product shots.

Importance: MEDIUM

?
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Rokinon 21mm F 1 4 ED AS UMC CS vs the average camera lens

  • 1.4 lower f-number at telephoto end
    Rokinon 21mm F 1 4 ED AS UMC CS has a brighter maximum telephoto aperture than the average camera lens (f/1.4 vs f/2.8). The average lens has a maximum telephoto aperture of f/2.8.
    What it is: The widest aperture available at the long end of the zoom range, affecting light intake and background blur.
    When it matters: When you shoot at the long end in low light or want stronger background blur for portraits and sports.

    Importance: HIGH

    Rokinon 21mm F 1 4 ED AS UMC CS has a brighter maximum telephoto aperture than the average camera lens (f/1.4 vs f/2.8). The average lens has a maximum telephoto aperture of f/2.8.1.4 vs 2.8
  • Has aperture ring
    Rokinon 21mm F 1 4 ED AS UMC CS has an aperture ring, the average camera lens does not. 31.2% of camera lenses include an aperture ring.
    What it is: A dedicated ring on the lens used to control the aperture directly.
    When it matters: When you want direct tactile control over exposure while shooting photos or video.

    Importance: MEDIUM

    Rokinon 21mm F 1 4 ED AS UMC CS has an aperture ring, the average camera lens does not. 31.2% of camera lenses include an aperture ring.
  • Has focus distance scale
    Rokinon 21mm F 1 4 ED AS UMC CS has a focus distance scale, the average camera lens does not. 48.6% of camera lenses include a focus distance scale.
    What it is: A marked scale that shows the approximate focus distance set on the lens.
    When it matters: When you pre-focus manually for street, zone focusing, or repeatable tripod setups.

    Importance: MEDIUM

    Rokinon 21mm F 1 4 ED AS UMC CS has a focus distance scale, the average camera lens does not. 48.6% of camera lenses include a focus distance scale.
  • 12.7 mm narrower lens barrel
    Rokinon 21mm F 1 4 ED AS UMC CS is slimmer than the average camera lens (64.3 mm vs 77 mm). The average lens has a diameter of 77 mm.
    What it is: The widest outer diameter of the lens barrel.
    When it matters: When grip comfort, filter size, or fit inside a tight camera bag matters to you.

    Importance: MEDIUM

    Rokinon 21mm F 1 4 ED AS UMC CS is slimmer than the average camera lens (64.3 mm vs 77 mm). The average lens has a diameter of 77 mm.64.3 mm vs 77 mm
  • 1 more aspherical elements
    Rokinon 21mm F 1 4 ED AS UMC CS has more aspherical elements than the average camera lens (3 vs 2). The average lens has 2 aspherical elements.
    What it is: Specially shaped lens elements used to reduce distortion and improve sharpness with fewer optical compromises.
    When it matters: When edge sharpness and lower distortion matter in wide-angle, travel, or everyday shooting.

    Importance: MEDIUM

    Rokinon 21mm F 1 4 ED AS UMC CS has more aspherical elements than the average camera lens (3 vs 2). The average lens has 2 aspherical elements.3 vs 2
  • 1.4 lower f-number at telephoto end
    Rokinon 21mm F 1 4 ED AS UMC CS has a brighter maximum telephoto aperture than the average camera lens (f/1.4 vs f/2.8). The average lens has a maximum telephoto aperture of f/2.8.
  • 1 more aspherical elements
    Rokinon 21mm F 1 4 ED AS UMC CS has more aspherical elements than the average camera lens (3 vs 2). The average lens has 2 aspherical elements.
  • Has aperture ring
    Rokinon 21mm F 1 4 ED AS UMC CS has an aperture ring, the average camera lens does not. 31.2% of camera lenses include an aperture ring.
  • Has focus distance scale
    Rokinon 21mm F 1 4 ED AS UMC CS has a focus distance scale, the average camera lens does not. 48.6% of camera lenses include a focus distance scale.
  • 12.7 mm narrower lens barrel
    Rokinon 21mm F 1 4 ED AS UMC CS is slimmer than the average camera lens (64.3 mm vs 77 mm). The average lens has a diameter of 77 mm.
  • 1 fewer low-dispersion elements
    Rokinon 21mm F 1 4 ED AS UMC CS has fewer low-dispersion elements than the average camera lens (1 vs 2). The average lens has 2 low-dispersion elements.
  • No full-time manual focus
    Rokinon 21mm F 1 4 ED AS UMC CS does not support full-time manual focus, the average camera lens does. 68.4% of camera lenses support full-time manual focus.
  • Not weather-sealed
    Rokinon 21mm F 1 4 ED AS UMC CS does not support weather sealing, the average camera lens does. 50.3% of camera lenses support weather sealing.
  • Older release date
    Rokinon 21mm F 1 4 ED AS UMC CS was released earlier than the average camera lens.
    October 2015
  • Not weather-sealed
    Rokinon 21mm F 1 4 ED AS UMC CS does not support weather sealing, the average camera lens does. 50.3% of camera lenses support weather sealing.
    What it is: Protective sealing intended to resist splashes, dust, and light environmental exposure.
    When it matters: When you often shoot outdoors in light rain, dust, or changing conditions.

    Importance: HIGH

    Rokinon 21mm F 1 4 ED AS UMC CS does not support weather sealing, the average camera lens does. 50.3% of camera lenses support weather sealing.
  • No full-time manual focus
    Rokinon 21mm F 1 4 ED AS UMC CS does not support full-time manual focus, the average camera lens does. 68.4% of camera lenses support full-time manual focus.
    What it is: The ability to adjust focus manually without leaving autofocus mode.
    When it matters: When you want to fine-tune focus instantly without switching out of autofocus.

    Importance: HIGH

    Rokinon 21mm F 1 4 ED AS UMC CS does not support full-time manual focus, the average camera lens does. 68.4% of camera lenses support full-time manual focus.
  • 1 fewer low-dispersion elements
    Rokinon 21mm F 1 4 ED AS UMC CS has fewer low-dispersion elements than the average camera lens (1 vs 2). The average lens has 2 low-dispersion elements.
    What it is: Optical elements designed to reduce color fringing by controlling how different wavelengths focus.
    When it matters: When you want cleaner edges and less color fringing in high-contrast scenes.

    Importance: MEDIUM

    Rokinon 21mm F 1 4 ED AS UMC CS has fewer low-dispersion elements than the average camera lens (1 vs 2). The average lens has 2 low-dispersion elements.1 vs 2
  • 16% lower user score
    Rokinon 21mm F 1 4 ED AS UMC CS has a lower user score than the average camera lens (6.98 vs 8.091).
    What it is: A rating that combines user reviews and the total number of reviews received by the camera lens.
    When it matters: When real-world owner satisfaction and review volume matter to your decision.
    Rokinon 21mm F 1 4 ED AS UMC CS has a lower user score than the average camera lens (6.98 vs 8.091).6.98 vs 8.09
  • Older release date
    Rokinon 21mm F 1 4 ED AS UMC CS was released earlier than the average camera lens.
    October 2015
    What it is: The date when the lens model was first officially introduced.
    When it matters: When you prefer a newer optical design with more modern autofocus, coatings, or stabilization features.

    Importance: LOW

    Rokinon 21mm F 1 4 ED AS UMC CS was released earlier than the average camera lens.2015 vs 2016
  • 50.8% less popular
    Rokinon 21mm F 1 4 ED AS UMC CS is less popular than the average camera lens (4.23 vs 6.383).
    What it is: An indicator based on the number of reviews received by the camera lens.
    When it matters: When you want to see which camera lenses attract the most buyer attention and review activity.
    Rokinon 21mm F 1 4 ED AS UMC CS is less popular than the average camera lens (4.23 vs 6.383).4.23 vs 6.38

Graphic comparison of Rokinon 21mm F 1 4 ED AS UMC CS and

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Third-party reviews

(Reviews last updated: July 2026)

What customers like about Rokinon 21mm F 1 4 ED AS UMC CS?

  • Extremely strong image quality with great resolution even at wide apertures
  • Large f/1.4 aperture allows for excellent low-light performance and shallow depth of field
  • Compact and lightweight design that complements mirrorless camera bodies
  • High-quality physical and mechanical construction with a smooth, damped focus ring
  • Effective resistance to flare and low chromatic aberrations
  • 9-bladed aperture produces attractive bokeh and sunbursts
  • Minimal barrel distortion and well-controlled vignetting
  • Includes a lens hood and drawstring bag as standard accessories

What customers dislike about Rokinon 21mm F 1 4 ED AS UMC CS?

  • Fully manual focus with no electronic coupling, resulting in no EXIF data or lens profile support
  • Softness in the corners when shooting wide open at f/1.4
  • Lacks a hyperfocal scale on the barrel, which can be inconvenient for street photographers
  • Absence of weather sealing
  • Focus ring can be sensitive enough to be turned accidentally

Expert reviews

L
lenstip.com
08/12/2015
Summary of the review
E
ephotozine.com
06/10/2015
Summary of the review
W
whatdigitalcamera.com
24/02/2016
Summary of the review
D
dustinabbott.net
01/03/2016
Summary of the review
M
mirrorlessons.com
27/07/2016
Summary of the review
A
amateurphotographer.com
18/03/2023
Summary of the review
P
popphoto.com
20/05/2016
Summary of the review
T
trustedreviews.com
24/02/2016
Summary of the review
D
derjackistweg.de
06/03/2016
Summary of the review
L
lesnumeriques.com
03/05/2016
Summary of the review
D
digifotopro.nl
27/08/2016
Summary of the review

Video reviews

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