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Explore Scientific 25 mm - 100° Argon-Purged Waterproof 2" Eyepiece - EPWP10025-01

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SKU: EXS-EPWP10025-01
$849.99 $679.99
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Explore Scientific 25 mm - 100° Argon-Purged Waterproof 2" Eyepiece

  • The Explore Scientific 25 mm 100 Degree Eyepiece has a barrel size of 2" and has a focal length of 25 mm

  • Argon-purged and O-ring sealed resulting in 100% waterproof

  • Equipped with a replaceable soft, folding eyecup and weighs approximately 2.5 lb

  • Explore Scientific 25 mm 100 Degree Eyepiece features EMD coatings on all lens-to-air surfaces and they are full multi-coated

The Explore Scientific new 25 mm, 100 Degree field, 2" eyepiece is argon-purged and O-ring sealed to be 100% waterproof. Explore Scientific did various tests on ever eyepiece in one meter of water for 30 minutes to ensure perfect seal before shipping.

The Explore Scientific 25 mm eyepiece is superb under almost any weather conditions. With the internal sealing of the eyepiece and purging it with inert, dry argon gas prevents internal fogging in the eyepiece when observing at sub-freezing temperatures. In dusty climates, the sealing effectively keeps wind blown dust and fine particulates from entering the eyepiece body. If observing in a more humid climate, the sealing prevents growth of fungus on the internal lens elements. Overall, the complete sealing and testing of the Explore Scientific 25 mm eyepiece maximizes the life of the internal optical coatings while also making the eyepiece easier to clean.

The 25 mm Explore Scientific eyepiece has high contrast, comfortable eye relief, and full field sharpness - with well-controlled astigmatism, field curvature, and lateral color. Its optical system (using lenses of dense crown, light crown, dense flint, and lanthanum rare earth optical glasses) is designed for maximum field/medium power deep space use with telescopes having focal ratios down as low as f/4. It is exceptionally effective on nebulas with fast f/ratio reflectors, such as Dobsonians, as it gives both an i mmense field and a bright exit pupil (over 5.5 mm with the typical f/4.5 Dob). Convenient for moderate power globular and lunar cluster observing with Dobsonians is made possible with its very wide field. You will also have a much longer time to observe before the planet drifts out of the field and the scope has to be repositioned than you would with a 60, 70 or 82 degree field eyepiece. The Explore Scientific 25 mm eyepiece is a superb tool for observing nebulas, open clusters, globular clusters, and galaxy clusters with any telescope competent of using a 2" telescope.

The Explore Scientific 25 mm eyepiece has a 100 degree apparent field that is nearly 50% larger in area than an 82 degree field eyepiece. While you could resort to obtaining a similar true field with a longer focal length (but narrower apparent field) conventional eyepiece, the Explore Scientific 25 mm eyepiece has the benefits of the higher power and darker sky backgrounds that are inherent in its shorter focal length.

Shielding your eye from ambient light and improving the image contrast is a soft rolldown eyecup on your Explore Scientific 25 mm eyepiece. This eyepiece only fits 2" focusers and has a safety groove in the 2" chrome barrel allowing you to engage your focuser thumbscrew. This feature helps prevent the eyepiece from falling in the event that the thumbscrew accidentally loosens when observing. The Explore Scientific 25 mm eyepiece is backed by a one year warranty.