Explore Scientific 68° 24mm Waterproof Eyepiece

This item is out of stock and on backorder; please get in touch with us at products@astronomerswithoutborders.org for delivery deadlines.

Using advanced computer design, combinations of low dispersion and high refractive index optical glasses, and durable multilayer deposition coatings, Explore Scientific 62° Series Argon-Purged Waterproof extreme wide field eyepieces are optimized to produce high contrast, high resolution, and superior flat field characteristics. The visual effect of these eyepieces, with their long eye relief and 68° apparent field, is truly a full-immersion experience. The 62° Series eyepieces are parfocal (meaning they focus near the same point regardless of the focal length you select) and come with a removable and foldable soft silicone rubber eyecup for the observer's comfort. As experienced astronomers know, eye comfort is critical when trying to observe the visual limits of the telescope.

Protection from the Outdoors - By making the eyepiece body Argon-purged, the waterproof eyepiece internal elements will remain as pristine as the day they were assembled.

Argon atoms are larger than that of Nitrogen, and therefore, they are less likely to leak or diffuse their way through the seals over the life of the eyepiece. The atomic radius of Argon is larger than Nitrogen by 0.13 angstroms and has a larger atomic volume of 11.2 cubic centimeters/molecule. Argon also has superior inertness vs Nitrogen (i.e., forming few or no chemical compounds with other elements) that prevents adverse reactions with eyepiece components and, therefore, extends the longevity of the internal components and also prevent chemical reactions with other elemental contaminants that may be introduced through a weakened seal. And, finally, because Argon is less conductive of heat than Nitrogen, Argon cools slower, thereby buffering the effects of rapid temperature changes of the optics.

The sealed, dry environment is impervious to internal fogging and contaminants like fungus growing between the lens elements. Our waterproof eyepiece is easier to clean, and there is no risk of a cleaning solution migrating from the top of the lens and seeping around edges to be trapped between elements. To ensure a perfect seal, we test every eyepiece in one meter of water for 30 minutes.