Samyang 10mm F2.8 ED AS NCS CS

Construction and Handling

The build quality of the Samyang 10mm F2.8 lens is quite good.  All the various parts of the lens are manufactured to tight tolerances and apart from what we mentioned about the accessories on the previous page, there is nothing that might lead someone to think that this is a cheap(ish) lens.

87mm front element (click to enlarge)

With a diameter of 87mm, the front element on this lens is quite large.  It is convex in shape, though it doesn't bulge nearly as much as glass in the the Pentax 15mm F3.5 from the film era.  At its highest point (in the center), the front element only extends about a centimeter beyond its edge, and it still sits below the height of the small flaps of the built-in hood.  There is no front filter thread, so you cannot use any filters.

The built-in hood is made of plastic.  It sturdy but it could be made more durable, as we've noticed that the edges are easily scuffed, and the hood can bend slightly when squeezed with only a small amount of force.

The remainder of the lens consists of four parts: the focusing ring, the depth of field scale, the aperture ring, and the lens mount.

Samyang 10mm - Lens Barrel (click to enlarge)

The focusing ring features a printed distance scale with both metric and empirical markings.  The grip is made of rubber and provides plenty of friction, while the remainder of the ring is made of plastic.

The small piece of barrel directly below the focusing ring is made of metal.   It features a depth of field scale around which the lens name is engraved.

Next is the aperture ring, which is surrounded by a red decorative ring.  The aperture ring locks at the "A" setting and can be turned freely at other settings.  The ring itself is made of plastic, though the release button is made of metal and is finely machined.  Using the aperture ring, the aperture setting can be adjusted at half-stop intervals from F2.8 to F16; there is no physical intermediate stop between F16 and F22.

Since this lens only covers the APS-C digital format, the aperture ring is technically not needed, as the aperture can (and should) be controlled via the camera body whenever the ring is set to "A".  If you move the aperture ring to any other setting on a DSLR, the camera will indicate "F--" and you will have to stop-down meter in M mode to get the correct exposure.

10mm lens mount

The lens mount, which is made of metal, houses the contacts that transmit aperture information to the camera.  The rear element protrudes slightly and moves up to about a millimeter as you focus.

Samyang rear mount cap

The rear cap that comes with the 10mm uses a slightly different design than OEM Pentax caps, and it's not a snug fit on genuine Pentax lenses.  It also doesn't cover the electrical contacts, so we recommend using a Pentax cap instead to prevent damage to the mount.

Size, Weight, and Handling

The photo below shows the size of the Samyang 10mm beside the Pentax DA L 18-55mm kit lens.  As you can see, the two lenses are comparable in diameter and length if you disregard the 10mm's massive front element and hood.

The Pentax version of the Samyang 10mm weighs in at 580 grams, which is just below the weight of the K-50 DSLR.  This makes it light enough to carry around comfortably, though your kit may feel a little heavy after a while around your neck.

Samyang 10mm and Pentax 18-55mm

From a handling perspective, we have very few complaints about the 10mm.  The lens is easy to hold and carry, and it's compact enough to fit in small camera bags. If anything, the focusing ring could offer a little more friction, for while there is no play or looseness, the ring is quite easy to turn.

Product Photos

Refer to the photos below for more views of the 10mm.  Click on any thumbnail to enlarge and browse.

Verdict

In all but a few small areas, the Samyang 10mm ED AS NCS CS looks and feels like a premium lens.  It's relatively compact for what it is, and easy to hold and carry.

Our only major concern is with respect to manufacturing defects.  We had to order three copies of this lens to get one without flaws: the first suffered from de-centering, which resulted in one edge of the image being excessively blurry; the second had a loose hood and occasionally-stiff focusing ring.  While such a small sample size isn't necessarily indicative of a widespread quality control issue, we felt obliged to mention it.