Explore Scientific 68° Series 1.25" 20mm Waterproof Eyepiece

The 68° Series 20mm is a versatile general-purpose eyepiece built around a 6-element design of low-dispersion and high-refractive-index glasses that produces sharp, well-corrected images across the full 68° field. At moderate magnification, it handles everything from bright nebulae to galaxy cores with a wide, comfortable view. It has waterproof construction and premium coatings.

Key Features

• 6-element optics — precision-ground low-dispersion and high-refractive-index glasses deliver sharp, color-free images
• 68° apparent field of view — frames deep-sky objects with generous surrounding context for easier orientation and more immersive observing
• Argon-purged waterproof housing — sealed and fog-proof for dependable performance in dew, humidity, and temperature swings
• Multilayer deposition coatings on all air-to-glass surfaces with edge-blackened elements for high contrast
• Fold-down silicone rubber eyecup for comfortable extended viewing
• 1.25" barrel compatible with standard focusers across telescope types

Ideal For

• General-purpose deep-sky observing — open clusters, nebulae, and galaxies all benefit from the wide field and moderate magnification
• Star party workhorse — comfortable to use, wide field makes it easy for visitors to find the view, and the waterproof build survives dew-heavy nights
• Observers who value optical quality and want sharp, wide 68° views