Samyang/Rokinon 35mm f/1.4 AS UMC

SLRgear Review
November 13, 2012
by Andrew Alexander

Samyang is a Korean lens manufacturer which has taken to producing manual focus lenses in a variety of mounts under both its own name and several others, including Rokinon, Bower and Pro Optic. The 35mm ƒ/1.4 UMC was announced in March of 2011.

The Rokinon 35mm ƒ/1.4 UMC was designed to fit the full-frame 35mm sensors of Nikon, Canon and Sony cameras, as well as having models available in Pentax, Samsung NX and four-thirds mounts. On a APS-C sized sensor, the lens will produce an effective field of view of approximately 56mm (Canon) or 52mm (Nikon, Sony, Samsung or Pentax); on a four-thirds mount, the lens will produce an effective field of view of approximately 70mm.

We've been wanting to test the Samyang lenses for some time and a special thanks goes out to LensRentals.com for sending us a selection to test. The Rokinon 35mm ƒ/1.4 ships with a petal-shaped lens hood and is available new for around $500.

Sharpness
The Rokinon 35mm ƒ/1.4 UMC produces surprisingly sharp results, even when used at its wider apertures, though it must be stopped down slightly for maximal sharpness.

Mounted on the full-frame Canon 1Ds mkIII, the lens produced moderately sharp images when used wide open at ƒ/1.4, with a character I might describe as murky and uneven: it's not a consistent sharpness, so ƒ/1.4 is not the aperture to use for delicate capture work. Stopping down to ƒ/2 improves sharpness across the frame and evens out this murkiness; it's quite sharp in the center of the frame. Further to ƒ/2.8, one could be extremely happy with the performance you get from a $500 lens, with very sharp results from corner to corner, but when you stop down to ƒ/4, you get tack-sharp results across the frame. This performance continues through to ƒ/8, and diffraction limiting begins to set in at ƒ/11, but you don't see the impact of this until ƒ/16, where a generalized softness begins to descend upon the image. When stopped down to ƒ/22 and ƒ/32 you get a bit more softness, but nothing more than you might expect at those small apertures.

Mounted on the subframe Canon 7D, performance for sharpness is very similar, perhaps a bit more forgiving at the ƒ/1.4 setting. Overall, we're extremely impressed at the results obtained with this very economical lens.

Chromatic Aberration
The Rokinon 35mm ƒ/1.4 UMC provides a very good level of resistance to chromatic aberration, and it's fairly constant across the range of apertures (if you see it, you'll see it in the corners in areas of high contrast).

Even more noteworthy is a low amount of longitudinal chromatic aberration, which is typical of very fast lenses (ie., ƒ/1.4 or faster). This CA is evident in this lens, showing as magenta / green fringing on areas outside the plane of focus, but its not as prevalent as other fast glass we have tested.

Shading (''Vignetting'')
Corner shading isn't really a problem on the sub-frame Canon 7D, with the only noteworthy results being extreme corners that are 1/3EV darker than the center, when set to ƒ/1.4. At any other setting, light falloff is insignificant.

On the full-frame 1Ds mkIII however, it's somewhat more significant: at ƒ/1.4 light falls off to make the extreme corners almost a full stop darker than the center; at ƒ/2, this falloff lowers to around 2/3EV. At ƒ/2.8 and smaller apertures, falloff results are a quarter-stop or less, which isn't really significant.

Distortion
The 35mm ƒ/1.4 UMC does fairly well to restrict distortion, showing a consistent +0.3% barrel distortion in the corners when mounted on the Canon 7D. On the 1Ds mkIII, there's slightly more distortion, with a maximum result of +0.6%

Autofocus Operation
The Rokinon 35mm ƒ/1.4 is not equipped with autofocus.

Macro
The lens isn't designed as a macro lens, but provides 0.2x magnification when used at its minimum close-focusing distance of just under 12 inches.

Build Quality and Handling
The Rokinon 35mm ƒ/1.4 UMC is fairly large for a prime lens, at 698 grams (24.6 oz). The lens is black with a slightly stipled finish and has a red accent ring near the mount. The lens mount is metal and the 77mm filter threads are plastic.

Without autofocus, the lens makes up for this shortcoming by providing a detailed feature set. The lens has an aperture ring with half-stop click marks, however there is no locking feature to keep the lens locked at its smallest aperture for modern cameras. The lens has a distance scale marked in feet and meters, as well as a fairly comprehensive depth-of-field scale (showing marks for ƒ/2.8, ƒ/5.6, ƒ/11, ƒ/16 and ƒ/22) but no infrared index marker.

The 1 1/2-inch wide focus ring is rubber, a series of ribs running parallel to the body of the lens. The focusing range ends in hard stops at the infinity and close-focusing ends of the lens; the lens will focus past infinity. There is no lens extension during focusing, and the front element does not rotate. The lens uses eight diaphragm blades to make up the aperture.

The petal-shaped lens hood is around 2 inches in depth. The hood is a bayonet-mount that reverses onto the lens for easy storage. The lens is nicely resistant to obvious flare from bright light sources such as the sun, but the hood works well to reduce generalized veiling flare.

Alternatives

Nikon 35mm ƒ/1.4G ~$1,800
Despite being over three times the price, we found the Rokinon to be on an aperture-to-aperture basis a sharper lens, with the Rokinon 35mm producing tack-sharp results the Nikon 35mm could not. Chromatic aberration is also a bit lower: vignetting and distortion results are about the same. Of course with the Nikon, you get autofocus.

Canon 35mm ƒ/1.4L USM ~$1,400
More expensive than the Rokinon, the Rokinon was able to produce images that were slightly sharper than the Canon, though some stopping down was required: at wide apertures, the Canon has intense corner softness. Again, the Canon has autofocus and a higher build quality than the Rokinon.

Carl Zeiss 35mm ƒ/1.4 Distagon ~$1,800
We haven't yet tested this expensive Carl Zeiss glass, which also does not have autofocus.

Pentax 21mm ƒ/3.2 Limited SMC P-DA ~$550
The Pentax 21mm would produce a similar field of view as the Rokinon 35mm; it produced almost as sharp results, with similar results for CA, distortion and corner shading. The Pentax is equipped with autofocus and is a much smaller and more portable lens.

Sigma 35mm ƒ/1.4 DG HSM "A" ~$900
Sigma has recently produced this similar lens, which we have not yet had the opportunity to test.

Sony 35mm ƒ/1.4 G SAL-35F14G ~$1,300
Sony's offering in this category proved to be sub-par, with very soft results wide open at f/1.4.

Conclusion
It's a crowded field in the fast 35mm lens market, and Samyang's approach to make an economical manual focus lens was a wise one: if you don't need autofocus, but want the razor-thin depth-of-field of a fast lens, the lens was already in your crosshairs. Our testing shows that it is also remarkably good optically, producing sharp images with very low chromatic aberration.

Product Photos

Sample Photos

The VFA target should give you a good idea of sharpness in the center and corners, as well as some idea of the extent of barrel or pincushion distortion and chromatic aberration, while the Still Life subject may help in judging contrast and color. We shoot both images using the default JPEG settings and manual white balance of our test bodies, so the images should be quite consistent from lens to lens.

Still Life shot

VFA target

As appropriate, we shoot these with both full-frame and sub-frame bodies, at a range of focal lengths, and at both maximum aperture and ƒ/8. For the ''VFA'' target (the viewfinder accuracy target from Imaging Resource), we also provide sample crops from the center and upper-left corner of each shot, so you can quickly get a sense of relative sharpness, without having to download and inspect the full-res images. To avoid space limitations with the layout of our review pages, indexes to the test shots launch in separate windows.