Explore Scientific 92° ED Series 20mm Waterproof Eyepiece

Ultra-wide-field eyepieces at the 92° class have traditionally been heavy, expensive, and limited to a few focal lengths. The Explore Scientific 92° ED Series 20mm Waterproof Eyepiece delivers a 92° apparent field of view with extra-low dispersion glass, waterproof argon-purged construction, and long eye relief — immersive panoramic viewing without the weight premium of older ultra-wide designs.

The ED glass reduces color fringing that plagues standard ultra-wide eyepieces, especially at the field edges where chromatic aberration is most visible. At 92°, the apparent field is wide enough to create a genuine sense of being immersed in the star field rather than looking through a window. The waterproof, argon-purged housing is built for all-night sessions regardless of humidity or dew conditions.

Key Features

• Extra-low dispersion glass — minimized chromatic aberration for clean, high-contrast views across the full 92° field
• 92° apparent field of view — among the widest available, creating a truly immersive observing experience
• Waterproof and argon-purged — sealed against moisture and internally fog-proof
• Long eye relief — comfortable for extended sessions and eyeglass-compatible
• 2" barrel — maximum light throughput and field stop diameter for ultra-wide-field performance
• Enhanced multi-layer deposition coatings on all air-to-glass surfaces

Ideal For

Medium magnification with an immersive panoramic field — ideal for extended nebulae and open clusters. The 92° field transforms the observing experience — targets fill the eyepiece rather than floating in empty space. An ideal upgrade for Dobsonian owners, deep-sky visual observers, and anyone who values the immersive experience of panoramic astronomical viewing.