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Explore Scientific  |  SKU: EPWP6828–01

Explore Scientific 68° Series 2" 28mm Waterproof Eyepiece


Bonus offer: after adding this item to cart, add 3 other eyepieces + the soft-sided case to get it for Free ($49.99 value)

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Explore Scientific 68° Series 2" 28mm Waterproof Eyepiece



  • 28mm Focal Length
  • 68° Field of View
  • 2" Diameter Barrel
  • Fully Multi-coated Optics
  • Argon-Filled, Water and Fogproof
  • Slip-Resistant Textured Surface
  • Fold-Down Eyecup


Experience the Universe with Unparalleled Clarity and Comfort

The Explore Scientific 68° Series 2" 28mm Waterproof Eyepiece is crafted for the astronomy enthusiast who seeks to merge expansive celestial vistas with exquisite detail. This eyepiece leverages state-of-the-art optical technology to offer an observational experience that is both broad and deeply immersive.

  • Expansive 28mm Focal Length: Captures wide swaths of the night sky, making it ideal for studying complex star fields, nebulae, and galaxies in stunning clarity.
  • Wide 68° Apparent Field of View: Offers a vast, immersive perspective of space, drawing you into the cosmos for an unparalleled viewing experience.
  • Supreme Optical Quality: Engineered with low dispersion, high refractive index glasses, and coated with durable multilayer deposition coatings, this eyepiece delivers sharp contrast, high resolution, and a flat field without compromise.
  • Ergonomic Design for Extended Viewing: Features long eye relief and a fold-down eyecup to ensure maximum comfort for all observers, including eyeglass wearers.
  • Robust and Reliable: Argon-filled, waterproof, and fogproof construction protects against the elements, preserving the pristine condition of internal optics. The slip-resistant textured surface enhances grip and usability.

Advanced Optical Engineering for Deep Sky Exploration

Designed using sophisticated computer algorithms, the 68° Series eyepiece is optimized for a full-immersion visual experience, enabling the discovery of faint celestial details with ease. Its parfocal capability allows for seamless transitions between eyepieces without the need to refocus, making your stargazing sessions more efficient and enjoyable.

Durable Protection Against the Elements

The argon-purged enclosure ensures the eyepiece's longevity, offering superior protection over traditional nitrogen-filled models. Argon's large atomic size and low thermal conductivity mean your views remain clear and stable, even with temperature fluctuations, ensuring every observation is as breathtaking as the first.

Easy Maintenance, Lasting Performance

Each eyepiece undergoes rigorous waterproof testing to guarantee its seal integrity, making maintenance simple and worry-free. The design prevents internal fogging and protects against contaminants, ensuring that your eyepiece remains a reliable companion for years of cosmic exploration.

Embark on a Journey of Discovery

The Explore Scientific 68° Series 28mm Eyepiece is not just an optical tool; it's a window to the wonders of the universe, designed for those passionate about unlocking the mysteries of the night sky.

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Explore Scientific 68° Series 2" 28mm Waterproof Eyepiece | EPWP6828–01 | 812257010516

Explore Scientific 68° Series 2" 28mm Waterproof Eyepiece






Focal Length

28 mm

Focal Ratio


Field of View



Enhanced multi-layer deposition (EMD) coatings

Argon-purged, water and fog proof

21.6mm eye relief

31.8mm field stop diameter

Barrel Size



91.4mm length

61.3mm width


458 g | 16.1 oz
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