Explore Scientific 68° Series 1.25" 20mm Waterproof Eyepiece

The 68° Series 20mm is a versatile general-purpose eyepiece built around a lanthanum glass optical design 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. Waterproof construction and premium coatings at $109 place it well above entry-level quality.

Key Features

• Multi-element lanthanum glass optics — precision-ground dense crown, light crown, dense flint, and lanthanum 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
• Enhanced Multi-Layer Deposition (EMD) 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 lanthanum glass performance without the cost of ultra-wide-field designs