Explore Scientific 68° Series 2" 40mm Waterproof Eyepiece

Explore Scientific 68° Series 2" 40mm Waterproof EyepieceThe 68 Series 40mm is the flagship of the line maximum focal length, 2" barrel, and lanthanum glass optics delivering the widest, brightest views the series offers. With a 68 field of view at 40mm, you are looking through an expansive window onto the sky. Generous eye relief keeps viewing comfortable even during long sessions. At $289 with argon purged waterproof construction and premium multi element optics, it undercuts comparable 2" wide field

The 68° Series 40mm is the flagship of the line — maximum focal length, 2" barrel, and lanthanum glass optics delivering the widest, brightest views the series offers. With a 68° field of view at 40mm, you are looking through an expansive window onto the sky. Generous eye relief keeps viewing comfortable even during long sessions. At $289 with argon-purged waterproof construction and premium multi-element optics, it undercuts comparable 2" wide-field eyepieces from other manufacturers.

Key Features

• 2" barrel with 40mm focal length — the longest focal length in the series for maximum sky coverage and brightness
• Multi-element lanthanum glass optics — dense crown, light crown, dense flint, and lanthanum glasses produce sharp, color-corrected images across the full 68° field
• 68° apparent field of view — the widest framing in the 68° series for sweeping panoramic views of the sky
• Generous eye relief for relaxed, comfortable viewing during extended sessions, fully compatible with eyeglasses
• Argon-purged waterproof housing — sealed and fog-proof for dependable all-weather durability
• Enhanced Multi-Layer Deposition (EMD) coatings on all air-to-glass surfaces with edge-blackened elements for contrast

Ideal For

• Wide-field deep-sky observers framing the largest targets — the Pleiades, the full Orion Nebula region, Andromeda Galaxy, and sweeping Milky Way panoramas at their most expansive
• Maximum sky coverage with premium optics — ideal for initial target location, casual scanning, and simply enjoying the breadth of the night sky through quality glass
• 2" focuser owners who want the widest, sharpest views their equipment can deliver at an accessible price compared to ultra-wide-field alternatives