PENTAX SP 10×50 WP

The PENTAX SP 10×50 WP is a Porro-prism binocular designed for outdoor observation, birdwatching, and general nature viewing. Its 10× magnification brings distant subjects closer, while the 50 mm objective lenses gather light for viewing in a range of outdoor lighting conditions. The 5.0° real field of view provides a defined viewing area, and the 20 mm eye relief is a key consideration for users who observe while wearing eyeglasses.

The optical system uses BaK-4 Porro prisms and fully multi-coated optics. The traditional Porro-prism configuration provides a distinctive binocular design, while the multi-layer lens coatings are intended to reduce reflections and improve light transmission through the optical system. A 5 mm exit pupil and a stated relative brightness value of 25 complete the main optical specifications. The minimum focusing distance is approximately 18.15 feet, making the binoculars more suitable for observing subjects at a distance than for close-range viewing.

The SP 10×50 WP has a rugged body with waterproof construction and nitrogen filling. According to the manufacturer, its waterproof rating is JIS Class 6, with protection for submersion up to 1 meter. The binoculars weigh approximately 37.4 ounces and measure about 7.0 × 7.2 inches, with a thickness of 3.1 inches. These dimensions and the 50 mm objectives are important considerations for anyone choosing binoculars for extended outdoor use.