
Explore Scientific 20mm 52° Series Waterproof Eyepiece
Manufacturer Part # EPWP5220-01
Manufacturer Part # EPWP5220-01
If you're looking for an eyepiece that delivers a balance of wide-field immersion, edge-to-edge sharpness, and premium build quality, the Explore Scientific 20mm 52° Series Eyepiece is a stellar choice. Designed for both beginner and experienced astronomers, this mid-power eyepiece provides exceptional contrast and image fidelity, making it an ideal match for a wide range of telescopes.
With a 52-degree apparent field of view, this eyepiece gives you a comfortable balance between magnification and sky coverage. It's an excellent option for scanning deep-space objects, such as star clusters, nebulae, and galaxies, while still delivering tack-sharp planetary detail when used with longer focal length telescopes. The multi-element optical design ensures stars remain crisp across the field, and the generous 20mm focal length provides comfortable eye relief, making it an excellent choice for extended observation sessions.
Unlike many eyepieces that use nitrogen purging, Explore Scientific takes durability a step further by argon-purging this eyepiece. Argon molecules are larger and less likely to diffuse over time, meaning the interior optics stay moisture-free and protected from internal fogging, even in humid environments. This weather-resistant design also guards against dust and fungal growth, ensuring your eyepiece remains in top optical condition for years to come.
Explore Scientific employs proprietary EMD (Enhanced Multi-Layer Deposition) coatings on all optical surfaces, significantly reducing reflections and boosting light transmission. The result? High contrast, superb brightness, and minimal ghosting—essential qualities for both deep-space and planetary viewing. Whether you're admiring the intricate details of the lunar surface or tracing the delicate structure of the Orion Nebula, this eyepiece delivers a brilliantly clear and immersive experience.
The 20mm eye relief makes this eyepiece particularly friendly for eyeglass wearers, allowing them to view the full field without removing their glasses. The adjustable twist-up eyecup helps fine-tune the eye positioning for maximum comfort, ensuring you can enjoy prolonged observing sessions without unnecessary strain.
Explore Scientific constructs their eyepieces with high-quality aluminum and stainless steel, giving them a solid, premium feel without adding unnecessary bulk. The 1.25" barrel fits most standard focusers and includes a threaded base for compatibility with 1.25" astronomical filters, allowing you to enhance contrast for planetary or deep-sky viewing. The blackened lens edges further eliminate stray reflections, enhancing contrast and image purity.
The Explore Scientific 20mm 52° Argon-Purged Eyepiece is an exceptional mid-power eyepiece that fills a crucial focal length gap in any collection. Whether you're looking for an upgrade over stock eyepieces or a high-quality option for wide-field and planetary views, this eyepiece offers outstanding performance at a competitive price. With durable construction, premium coatings, and argon-purging for long-term reliability, it's a solid investment for serious observers.
Ready to enhance your viewing experience? Add this Explore Scientific 20mm 52° Series Eyepiece to your collection today and enjoy sharper, more immersive stargazing for years to come.
Item Number | EPWP5220–01 |
Focal Length | 20mm |
Length | 71mm |
Width | 43mm |
Weight | 181.4 grams; 6.4 oz. |
Barrel Size/Type | 1.25" O.D. / Double Taper |
Eye Relief | 15mm |
Field Stop Diameter: | 18.2mm |
Coatings: | EMD (Enhanced Multi-Layer Deposition) on all lens-to-air surfaces |
Lens Elements/ Groups | 5 Elements in 3 Groups; Edge Blackened |
Filter Thread | Fits Standard 1.25-inch Dia. Thread in Filters (1.125-inches x 42 TPI) |
Waterproof | O-Ring Sealed Argon Gas Purged; Tested Under 1 Meter of Water for 30 Minutes |
Eyecup | Removable Flip-Down Style Soft Silicone Rubber |
Lens Caps | Slide-on Top and Bottom |
Materials | Optical Glass; Aluminum; Steel; Silicone Rubber |
Markings | Laser Engraved: Focal Length; Series; Serial Number; Brand |
Barrel Size | 1.25" |
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Eye Relief | 15mm |
Field of view | 52° |
Field Stop | 18.2mm |
Focal Length | 20mm |
Number of optical elements | 5 |
Weight | 6.4 oz |
Warranty | 1 year |
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