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Explore Scientific  |  SKU: EPWP5220-01

Explore Scientific 52° Series 1.25" 20mm Waterproof Eyepiece

$119.99 $143.99

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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Ships from US warehouse in 1-2 business days

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Explore Scientific 52° Series 1.25" 20mm Waterproof Eyepiece



  • 20mm Focal Length
  • 52° Apparent Field of View
  • 1.25" Diameter Barrel
  • Fully EMD Multi-Coated Optics
  • Argon-Filled, Water and Fogproof
  • Slip-Resistant Textured Surface
  • Fold-Down Eyecup


Embark on a Celestial Journey with Optimal Field of View

The Explore Scientific 52° Series 1.25" 20mm Waterproof Eyepiece is a gem for amateur astronomers, offering a versatile focal length that's ideal for a wide range of observational needs. From participating in the Messier Marathon to exploring the Herschel Catalog, this eyepiece brings the universe to your doorstep with clarity and ease.

  • Ideal 20mm Focal Length: Produces a true 1-degree field of view with the ED127 at f7.5, perfect for capturing large swaths of the night sky and diving deep into celestial catalogs.
  • Expansive 52° Apparent Field of View: Immerse yourself in the cosmos with a wide-angle perspective that enhances your ability to locate and enjoy celestial objects.
  • Superior Optical Quality: Fully EMD Multi-Coated Optics ensure maximum light transmission, resulting in bright, sharp images with excellent contrast.
  • Durability Meets Convenience: Argon-filled, water and fog-proof design guarantees clear views under any conditions. The slip-resistant textured surface and fold-down eyecup add to its ergonomic design.

Enhanced Viewing with Averted Vision

This 20mm eyepiece is specially designed to improve your observation of faint objects. Utilizing the technique of averted vision, it allows you to see dimmer celestial bodies by looking slightly aside, leveraging the more light-sensitive regions of your eyes for better visibility.

Perfect Companion for Binoviewers

Its compact size and optimal magnification range make the 52° Series 20mm eyepiece an excellent choice for most binoviewers, offering a balanced and comfortable viewing experience without compromising on quality.

Transform Your Astronomy Experience

Whether you're navigating through star clusters, tracking nebulae, or simply enjoying the moon's craters, the Explore Scientific 52° Series 20mm Eyepiece is designed to enhance every moment under the stars. It promises exceptional quality and value, surpassing comparably priced eyepieces and becoming a crucial part of your astronomical toolkit.

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Explore Scientific 52° Series 1.25" 20mm Waterproof Eyepiece | EPWP5220-01 | 811803030053

Explore Scientific 52° Series 1.25" 20mm Waterproof Eyepiece

$119.99 $143.99





Focal Length

20 mm

Focal Ratio


Field of View



Enhanced multi-layer deposition (EMD) coatings

Argon-purged, water and fog proof

15mm eye relief

18.2mm field stop diameter

Barrel Size



71mm length

43mm width


181.4 g | 6.4 oz
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