Samyang 16mm F2 ED AS UMC CS

Focusing

The sturdy build quality of this lens and well-dampened focusing ring make this lens easy to focus in the field. Samyang spared no marks on the operating of this manual focus lens. The focusing ring has around 120 degrees of throw and nearly ¾ of that is for distances less than a meter. This lens can produce a very shallow depth of field at close focus distances.

The Samyang 16mm F2.0 focusing rings and lens barrel

When focusing at objects more than a meter away, focusing through the viewfinders works well but should always be checked in live view or by file preview when using large apertures. Its shallow depth of field and wide field of view  can make it tricky to nail the focus in this range of focusing.

The focus ring rotates clockwise to infinity as you operate it, fitting in with the standard for Pentax lenses. Focusing this lens feels more like an older, well manufactured lens than compared to the Pentax 15mm F4.0, which is light but lacks the sturdy feel of this manual focus system.

Verdict

The Samyang 16mm F2.0's manual focusing ring stands out remarkably well when compared to the Pentax 15mm Limited. While the autofocus of the Pentax is incredibly convenient, the smooth turn of the Korean made Samyang trumps the focusing quality of the Pentax in both dampening and precision. At wide apertures and long distances, we recommend a tripod and live view to double-check sharpness.  At smaller apertures, the hyperfocal distance allows the users to "set it and forget it" when it comes to focusing.