Featuring HD and Aero Bright Coatings to optimize light transmittance and minimize reflections, this medium telephoto lens offers a focal length of approximately 71mm (or approximately 56mm when mounted on a PENTAX 645 film-format camera body) in the 35mm format. By incorporating two ED (extra-low dispersion) elements and one glass-molded aspherical element in its optics, it assures high-resolution image reproduction over the entire image field, while effectively minimizing chromatic aberration, a problem commonly associated with fast lenses. This is the first lens to incorporate the PENTAX-innovated SR (Shake Reduction) mechanism within the lens barrel. This mechanism effectively compensates for camera shake up to approximately 3.5 shutter steps, assuring sharp, blur-free images even under conditions prone to camera shake, such as when handholding the camera in poorly lit locations without flash illumination, or when photographing sunset scenes.
This is a medium telephoto lens that is ideal for portraits that present clear, soft detailed images. This lens combines use of the new "HD Coating" and "Aero Bright Coating" for delivering a dramatic reduction in reflections and high transmissivity. The optical system uses extra-low dispersion (ED) glass and aspherical lenses for effectively correcting various types of aberrations. This lens provides high-resolution performance to the edges of the image. Macro photography at a maximum shooting magnification of 0.5X is also possible for taking still life photography. This lens incorporates PENTAX's first image stabilizer mechanism "SR" within the lens, and about 3.5 levels of image stabilizer correction are used for enabling sharp images without blurring during handheld shooting. A dust-resistant and drip-proof "AW (All Weather)" construction allows exceptional weather resistant performance. The lens also features a Quick-Shift Focus System enabling quick switching between AF and MF, round iris diaphragm for natural out-of-focus (bokeh) effect up to F5.6, and SP coating for repelling oil and dirt on the lens front surface.