Samyang/Rokinon 85mm f/1.4 AS IF UMC

SLRgear Review
November 19, 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 85mm ƒ/1.4 Aspherical was announced in 2009.

The Rokinon 85mm ƒ/1.4 Aspherical 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 136mm (Canon) or 128mm (Nikon, Sony, Samsung or Pentax); on a four-thirds mount, the lens will produce an effective field of view of approximately 170mm.

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 85mm ƒ/1.4 ships with a round lens hood and is available new from between $300-400.

Sharpness
Mounted on the sub-frame Canon 7D, the lens provides decently sharp performance when used wide open at ƒ/1.4; stopping down to ƒ/2 improves overall sharpness very slightly. Stopping down to ƒ/2.8 provides excellent results for sharpness, and at ƒ/4 we see tack-sharp results across the frame. This stays true through to ƒ/11, where diffraction limiting begins to set it, but is for all practical purposes still tack-sharp. At ƒ/16 diffraction limiting begins to rob the image of sharpness, and it is fairly apparent at ƒ/22.

Mounted on the full-frame Canon 1Ds mkIII, the lens doesn't perform quite as well, as the corners are a bit less forgiving. Results for sharpness when the lens is used wide open at ƒ/1.4 are acceptably sharp, but there is an uneven quality to the image. Stopping down does help to remove this uneven quality and improve overall sharpness: at ƒ/2 there is a slight improvement to central sharpness (at the cost of corner softness, suggesting our sample of this lens was de-centered). At ƒ/2.8, we see the same substantial sharpness improvement we saw with the 7D; the corners still show some light corner softness, but the center of the frame is excellent. At ƒ/4 we can see why the 7D showed tack-sharp results across the frame; it can't see the softer corners. In this respect many portrait lenses would like to have this profile, which emphasizes the center of the frame, and thus the subject, while softening the edges; however, the photographer employing them would probably prefer that this level of sharpness was visible at the ƒ/2 or ƒ/2.8 aperture settings.

Stopping down further produces no further improvement in sharpness, and no further reduction in corner softness, and diffraction limiting results are similar to what was noted above with the 7D.

Chromatic Aberration
The Rokinon 85mm ƒ/1.4 Aspherical 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).

The 85mm ƒ/1.4 suffers, as do most ''fast'' lenses, from problems with longitudinal chromatic aberration, where fringes of red and green are found near the plane of focus when the lens is used at wider apertures. This is easily viewed on the sample images taken with this lens, as magenta fringing when used at the ƒ/1.4 aperture setting.

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 around 3/4 EV 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 85mm ƒ/1.4 is very well designed, providing no significant distortion.

Autofocus Operation
The Rokinon 85mm ƒ/1.4 is not equipped with autofocus.

Macro
The lens isn't designed as a macro lens, providing only 0.08x magnification when used at its minimum close-focusing distance of just over three feet.

Build Quality and Handling
The Rokinon 85mm ƒ/1.4 Aspherical is a small optic, weighing 559 grams (19.7 oz). The lens is black with a slightly stipled finish and has a gold accent ring near the front. The lens mount is metal and the 72mm filter threads are plastic.

Generally, the Rokinon 85mm ƒ/1.4, when mounted on the camera body, will provide absolutely no information to the camera, meaning the camera will generally only work in Manual mode. Advanced features like in-body image stabilization may not work. Rokinon does produce a Nikon version of the lens with a CPU chip that allows the lens to communicate with the camera, and use the standard P/A/S/M modes.

The lens provides only a very basic 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. Also, there are no half-stops between ƒ/1.4 and ƒ/2, and none between ƒ/16 and ƒ/22. The lens has a distance scale marked in feet and meters, but no depth-of-field scale, or infrared index marker.

The inch-wide focus ring is rubber, a series of ribs running parallel to the body of the lens. The focusing ring provides around 140 degrees of turn, and the range ends in hard stops at the infinity and close-focusing ends of the lens. 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 round lens hood is around 1 1/2 inches in depth. The hood is a bayonet-mount that reverses onto the lens for easy storage.

Alternatives

Nikon 85mm ƒ/1.4G ~$1,700
The Nikon 85mm ƒ/1.4G provides a sharper image, but similar results for corner shading and distortion. Chromatic aberration is better lateraly (color shifts in the corners) but there is some evidence of longitudinal CA (color shifts at very wide apertures). The Nikon also has autofocus, where the Rokinon does not.

Canon 85mm ƒ/1.8 USM ~$400
Canon doesn't actually make an ƒ/1.4 lens - it makes a really expensive ƒ/1.2 and a more economical ƒ/1.8. The ƒ/1.8 lens we tested (many years ago) didn't provide great results for wide-open sharpness, but stopped down it was a good performer; results for distortion, CA and corner shading are similar or slightly better than the Rokinon. Again, autofocus is built-in to the Canon lens.

Carl Zeiss 85mm f/1.4 Planar T* 1.4/85 ~$1,000
The Carl Zeiss 85mm provides a similar manual focus experience, though there is definitely a quality difference with regards to the feel of the Carl Zeiss 85mm - it is silky smooth. The Zeiss lens is substantially more expensive, and there is indeed a more even sharpness when mounted on full-frame.

Pentax 55mm f/1.4 SDM SMC DA* ~$800
The Pentax 55mm provides an equivalent of around 83mm field of view on a Pentax digital body, so it would be the point of comparison for Pentax users. The lens provides very good sharpness at ƒ/1.4 and ƒ/2, and tack-sharp results at ƒ/2.8; Corner shading is minimal, but the lens provides slightly more CA and distortion. The Pentax 55mm also features autofocus.

Sigma 85mm f/1.4 EX DG HSM ~$1,000
The Sigma 85mm ƒ/1.4 provides a sharper image than the Rokinon, but similar results for corner shading and distortion. Chromatic aberration is better lateraly (color shifts in the corners) but there is some evidence of longitudinal CA (color shifts at very wide apertures). The Sigma also has autofocus, where the Rokinon does not.

Sony 85mm ƒ/1.4 Carl Zeiss Planar T* ~$1,700
The Sony 85mm ƒ/1.4 rivals Canon and Nikon glass as some of the sharpest we've tested, and is certainly sharper than the Rokinon 85mm. Similar issues as the others with regard to longitudinal chromatic aberration, but otherwise, distortion and corner shading are well-handled.

Conclusion
It's a crowded field in the fast 85mm 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 for not a lot of money, the lens was already on your radar. In this case Rokinon provides a good lens, but not a great lens: for most users who buy the lens to use it strictly at ƒ/1.4 they may be disappointed (and frustrated, as achieving focus with such a thin depth of field will be exceptionally difficult without autofocus). Stop down to ƒ/4 and you'll get excellent results with this lens, but you wouldn't buy this lens to use it at ƒ/4.

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 f/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.