Pentax 10×50 Z-Series ZD ED Binoculars

The image-enhancement starts with the 50mm objective lenses that draw in copious amounts of light and extend the practical useable ability well beyond smaller objective optics. The lenses are made with hybrid aspherical elements and extra-low dispersion (ED) glass. The aspherical elements eliminate distortion around the edges of the lens for clear edge-to-edge views and corrects lens astigmatism that can prevent the ability to bring subjects into sharp focus. ED glass corrects for chromatic aberration to ensure colors are accurately rendered. Anti-reflect fully multicoated optics maximize light transmission through the entire optical path to make views appear bright and crisp, especially in low light. Finally, the BAK4 roof prisms are phase-corrected to enhance contrast and further correct chromatic aberration. These technologies work together to produce bright and clear high-contrast images with virtually no distortion and accurate colors.

Complementing the optical performance is a housing that is built for a lifetime of rugged outdoor use. The optical tubes are nitrogen filled for fogproof performance and O-ring sealed to make the binoculars submersible to as much as 3.3′. A protective external lens coating helps to repel dust, water, and oil to ensure obstruction-free viewing. The larger objectives add weight and bias the center of balance forward which could lead to user fatigue and possible hand-shake, so for steadier views during longer glassing sessions, the binoculars are tripod mountable with an optional adapter.