Irix Lens 11mm F/4 Firefly (Pentax)

The Firefly version of the 11mm f/4 lens features a lightweight ABS plastic exterior construction that is sealed against moisture and dust along the main body of the lens. The Firefly construction also incorporates a rubber focus ring for improved grip and control, and has printed focus distance and depth of field scales to aid working with pre-focusing and hyperfocal focusing techniques.

Ultra wide-angle prime designed for full-frame Pentax-mount DSLRs, this lens can also be used on APS-C models where it provides a 16.5mm equivalent focal length.

Three aspherical, four high-refractive index, and two extra-low dispersion elements are featured within the optical design to limit both spherical and chromatic aberrations, as well as color fringing and distortion, for improved clarity, sharpness, and even illumination.

A Neutrino coating has been applied to limit lens flare and ghosting for improved contrast and color fidelity.

Manual focus designed is benefitted by a positive focus lock mechanism to secure your focus position at any point to limit unwanted shifting of focus.

A hard click stop indicates the infinity position on the focus ring for easy use in low-visibility conditions.

Large depth of field scale benefits using hyperfocal and pre-focus techniques.

Rear of the lens accepts 30 x 30mm cut gel filters.

Rounded nine-blade diaphragm contributes to smooth bokeh.