Explore Scientific 62° 40mm Waterproof Eyepiece - 2"

Low-Power Immersion: A 62° Flat-Field View at 40mm

With a 40mm focal length, this eyepiece is designed to be your primary tool for locating objects and framing large-scale celestial targets. The 62° apparent field of view offers a noticeably wider and more immersive window than standard Plössl designs, creating a "spacewalk" effect as you sweep through star fields. Its flat-field optics correct for distortions at the edge, keeping stars sharp across the entire view.

This design produces excellent contrast, making it easier to use averted vision to detect faint details in nebulae or the outer arms of galaxies. The near-parfocal design within the 62° series also means you'll spend less time refocusing when switching between eyepieces.

All-Weather Observing: The Argon-Purged, Waterproof Design

Unlike standard eyepieces, the Explore Scientific 62° 40mm is built to withstand challenging environmental conditions. The optical housing is sealed and purged with inert argon gas, which is more effective than nitrogen at preventing internal fogging over a wider temperature range. This means you can move the eyepiece from a warm room into the cold night air without losing your view to condensation.

This sealed construction also provides a permanent barrier against dust, moisture, and fungus, protecting the lens coatings and ensuring the eyepiece delivers high-contrast views for years. It's a robust, low-maintenance design for observers who don't let dew or humidity end their night.

Explore Scientific 62° 40mm vs. a Standard 2" Plössl

While a standard 2" 40mm Plössl eyepiece may be a simpler and less expensive option, the Explore Scientific 62° model offers distinct optical and mechanical advantages.

• Wider Apparent Field: The primary difference is the view itself. The ES 62° eyepiece provides a 62° apparent field, which is significantly more expansive than the typical 50° field of a Plössl, making observations more engaging.
• Edge-of-Field Correction: The flat-field design of the ES 62° delivers sharper star points at the edge of the field compared to a standard Plössl, which often exhibits some softness away from the center, especially in faster telescopes.
• Durability: The waterproof, argon-purged construction of the Explore Scientific eyepiece provides a level of environmental protection and longevity that is absent in non-sealed Plössl designs.