Samyang Announces 20mm F1.8 Lens in K-mount
Samyang expands their line of wide angle prime lenses
By PF Staff in Third-Party Announcements on Aug 11, 2016
Samyang has announced the Samyang 20mm F1.8 ED AS UMC fast ultra-wide angle lens in Pentax K-mount. The lens will also be available in various other mounts.
This new lens is a welcome addition to their already extensive line of wide angle lenses and is of particular interest for Pentax users, since Pentax currently offers no ultra wide angle prime lenses in the 24x36mm full-frame format. A 20mm focal length is suitable for landscape photography and for astro photography so this lens fills a void.
The lens has the KA variant of the K-mount which means that it is manual focus only and that it has an aperture ring with an "A" setting. It can thus be used on any and all Pentax bodies, film as well as digital, and supports all exposure modes provided by the body (P, Av, Tv, M, etc.).
The lens has a fast maximum aperture of F1.8 which makes it weigh in at a hefty 493 grams (17.4 oz). For comparison the discontinued and about 1.5 stops slower smc Pentax-FA 20mm F2.8 only weighs 255 g (9 oz). The Samyang measures 83 mm in diameter and is 87 mm from front to mount.
The 20mm F1.8 is provided with a petal shaped lens hood. This shape provides the optimal shielding of stray light from outside of the frame and thus helps reduce flare and ghosting.
The optics boast 13 elements in 12 groups. Two of the elements are aspherical and 3 are of ED glass. The filter size is 77mm and the closest focusing distance is 0.2 m (0.66 ft).
On a full frame camera the field of view is 94.8 degrees diagonally. On APS-C the field of view is reduced to 70.3 degrees which brings the lens out of the ultra wide class for APS-C users.
This new lens hasn't hit the stores yet, but when it does we will take a closer look at it and run it through its paces. Should you get hold of a copy we invite you to post a review here in our user review section.
The Samyang 20mm F1.8 lens is expected to also be marketed under other brand names hereunder Rokinon.