20MM 68° PURGÉ À L'ARGON / ARGON PURGED WATERPROOF
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 makes 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. The 68° Series eyepieces come with a twist-up rubber eye-guard that raise to the desired height for the comfort of the observer, and as experienced astronomers know, eye comfort is critical when trying to observe at the visual limits of the telescope.
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 offers, on all their eyepieces, an exclusive Five Year Limited Warranty.
Model : 20mm
Size : 1.25"
Eye relief :15.3mm
Elements : 6 in 4 Groups
34mm shown here