Product information "Pentax DA 15mm f/4.0 ED AL Limited Lens"
A high performance ultra wide lens for their digital SLR cameras, the Pentax smc-DA 15mm f/4 ED AL Limited provides the very best of optical performance in a little piece of camera jewelry for those demanding both the best images and the tiniest of packages. Like all of the Limited line, it comes in a distinct all-metal lens barrel and takes 49mm filters. Weighing under half a pound, it adds a different perspective to your premium kit.
The smc-DA ED AL's fit and finish is on par with the best in the world, and the optical system combines a 7-bladed aperture diaphragm with a hybrid aspherical lens element, an element of ED (Extra-Low Dispersion) glass, and Pentax's SP (Super Protect) external water and dirt-repelling lens coating for deliciously snappy results, even at f/4. This isn't a common mid-class zoom lens; it is truly created to be used effectively at its maximum f/4.0 aperture. The 86° field of view is equivalent to a 23mm lens in the old 35mm terms.
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