Pentax 2" XW Ultra Wide Angle Eyepiece - 16.5 mm Focal Length, 85° Field

Pentax XW16.5 2" Wide Angle Eyepiece - 16.5 mm Focal Length, 85° Field

The XW23 and XW16.5 models in the smc PENTAX XW series offer an extra-wide 85-degree angle of view and an extra-long 20 mm eye relief to deliver an exciting, wide-angle image.

High-grade optics for exceptional image quality

The eyepieces feature an optical system with 7 elements in 5 groups that outperforms the conventional XW series to obtain sharp star images right to the edge of the field of view. The high-performance optics contain lanthanum glass elements with high refractive power and exceptionally low dispersion, producing a balanced image with minimal aberrations. They are specifically designed to reduce the annoying blackout effect by effectively compensating for pupil spherical aberration.

Pentax-original multi-layer coating for outstanding light transmission efficiency

All lens surfaces that come in contact with air are treated with original multi-layer coatings, while all laminated surfaces are treated with an innovative partial coating to offer the light transmission efficiency of more than 90 percent (an astonishing 96 percent at 550 nm) over the visible light spectrum.

Advanced light-shielding technology for improved image contrast

Thanks to Pentax’s advanced computer simulation technology, the XW series features a light-shielding diaphragm at the most effective position to drastically reduce internal reflections for a brighter, higher-contrast image.

Comprehensive lineup to accommodate all applications

Featuring functional, practical focal lengths, the XW eyepiece series provides a comprehensive lineup that accommodates all types of applications, from low-magnification viewing of stars to high-magnification observation of planets.

Weatherproof construction for all-weather viewing

The XW series features JIS Class 4 weatherproof construction, making it possible to use it in drizzle or under night dew. However, please note that the XW-series eyepieces are not designed for underwater use and should not be submerged under water.

Standard eyepiece barrel size and built-In adapter-mounting thread

The XW series provides a choice of two installment diameters: standard 31.7 mm (1.25") version and 50.8 mm (2") version. When you remove the screw-on eyecup, the XW30-R and XW40-R models provide a screw thread with 48 mm diameter and 0.75 pitch, while other models provide a screw thread with 43 mm diameter and 0.75 pitch.