Explore Scientific 1.25 68° Series Argon-Purged Waterproof Eyepiece - 20mm

Explore Scientific 1.25" 68° Series Argon-Purged Waterproof Eyepiece - 20mm
Through computer-optimized design, a careful selection of optical glasses, and enhanced multi-layer deposition coatings, the Explore Scientific 68° Series eyepieces produce long eye-relief and ensure high image-correction, a flat field, and high contrast across the entire image field. An excellent choice for those who make extended visual studies of detail with subtle variations of brightness, and for those who must wear glasses while observing. With the introduction of the 68° Series, Explore Scientific has made two important improvements in eyepiece manufacture - the first being 15 layer Enhanced Multi-layer Deposition (EMD) coatings on all glass-to-air surfaces to gain maximum contrast, and waterproofing the eyepiece with the use of Argon gas purging instead of standard Nitrogen gas. Although Nitrogen is a fine choice that will last for many years, Argon is a larger molecule that maintains its protective properties over a wider range of temperatures, and is even more resistant to diffusion thereby further extending the protective waterproof environment of the eyepiece body. Each eyepiece is meticulously assembled into precision machined metal lens barrels that maintain the perfect alignment of the optical train for years of rugged use in the field. To keep internal reflections to a minimum, all internal surfaces of the eyepiece barrel are flat black, as well as the edges of the lenses themselves to minimize the scattering of light within the lenses themselves. Explore Scientific's eyepieces are backed with their exclusive Explore STAR Transferrable Extended Life of the Product Warranty. Limited Warranty is one year, which converts to the Explore STAR Transferrable Extended Life of the Product Warranty when product is registered within 60 days of purchase. We think that you will find Explore Scientific eyepieces rank among the finest obtainable and represent an outstanding value.

Focal Length 28mm Length 91.4mm Width 61.3mm Weight 16.1oz; 458g Barrel Size 2.00 Eye Relief 21.6mm Field Stop Diameter 31.8mm