An impressively wide prime lens, the Pentax K-mount 15mm f/2.4 Firefly Lens from Irix meshes an advanced optical design with a lightweight, durable physical construction. The expansive field of view is complemented by a sophisticated optical layout that utilizes low dispersion, aspherical, and high-refractive glass elements, as well as a Neutrino coating, to render imagery with low distortion, controlled spherical and chromatic aberrations, high contrast, and natural color rendering.
In addition to the imaging performance, this 15mm f/2.4 utilizes a manual focus design for fine-tuned control, and incorporates a unique positive focus lock to secure the focusing position at any point for consistent, repeatable shooting. As the Firefly version of this focal length, this lens is also distinguished by a lightweight ABS plastic exterior, printed lens markings, and weather-sealing about the lens housing to permit working in trying environmental conditions.
- The Firefly version of the 15mm f/2.4 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.
- Wide-angle prime designed for full-frame Pentax K-mount DSLRs, this lens can also be used on APS-C models where it provides a 22.5mm equivalent focal length.
- Two aspherical, three 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.
- Front of lens has 95mm-diameter filter threads and the rear of the lens accepts 30 x 30mm cut gel filters to lessen the likelihood of vignetting.
- Rounded nine-blade diaphragm contributes to smooth bokeh.