Explore Scientific 52° Series 2" 40mm Waterproof Eyepiece

The 52° Series 40mm is the widest-field eyepiece in the lineup, using a 2" barrel to frame expansive views of star fields and large deep-sky objects at the lowest practical magnification. Argon-purged waterproof construction and EMD coatings deliver reliable optical quality at a price that undercuts most 2" eyepieces on the market.

Key Features

• 2" barrel for maximum field of view — delivers noticeably wider views than any 1.25" eyepiece
• Argon-purged waterproof housing — sealed against moisture and fog for dependable all-weather observing
• Enhanced Multi-Layer Deposition (EMD) coatings on all air-to-glass surfaces for bright, high-contrast images at low magnification
• 4-element, 2-group optical design with edge-blackened elements to suppress stray light across the wide field
• Fold-down silicone rubber eyecup with comfortable eye relief for relaxed extended viewing, including with eyeglasses

Ideal For

• Wide-field deep-sky observers framing large targets like the Pleiades, Orion Nebula complex, or Andromeda Galaxy at their most expansive
• Telescope owners with 2" focusers who want to take full advantage of their equipment's field-of-view capability
• Star party and outreach use — low magnification and wide fields make it easy for visitors to find and enjoy bright objects