28mm Explore Scientific Eyepiece (68 deg.)

With the introduction of the 68° Series we are pleased to make 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. Through computer-optimized design, a careful selection of optical glasses, and enhanced multi-layer deposition coatings, the Explore Scientific 68° Series™ 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. All 68° Series eyepieces are fully EMD (Enhanced Multi-Layer Deposition) coated and edge-blackened to produce superior contrast.