Prime 25mm f/2.8 is designed for full-frame Pentax K-mount DSLR cameras, however can also be used with APS-C models where it provides a 37.5mm equivalent focal length.
Specifically developed for macro photography, this lens is designed for use within a 2.5:1 to 5:1 magnification range for producing greater-than-life-size imagery. This lens does not offer infinity focus.
When at 5:1 magnification, the lens has a minimum focusing distance of 6.8" along with a working distance of 1.6", which affords sufficient room for illuminating your subject. At the 2.5:1 position, a minimum focusing distance of 9.2" is possible along with a working distance of 1.8".
Wide-angle design benefits the high magnification design by providing greater depth of field compared to telephoto or long lens designs.
Manual focus operation for precise control over focusing distance when working with close-up subjects.
One extra-low dispersion element greatly reduces chromatic aberrations and color fringing for improved clarity and color accuracy.
Eight-blade diaphragm contributes to a pleasing out of focus quality when using shallow depth of field.
Especially slim and lightweight physical design is easier to use handheld and offers more room for illuminating close-up subjects.