The 100° apparent field yields a giant, "floating in space" feeling.  Argon-purged waterproof design w/sharp optics--you have a great eyepiece for general viewing of all objects.

• 25MM FOCAL LENGTH
• 100° APPARENT FIELD
• 8 ELEMENTS
• FLIP-UP RUBBER EYECUP
• COMFORTABLE EYE RELIEF
• RUBBER GRIP RING ON BARREL
• THREADED FOR FILTERS
• WATERPROOF
• DRY ARGON PURGED
• FULLY MULTI-COATED W/BBAR COATINGS

NOTE; NOT COMPATIBLE WITH CELESTRON LUMINOS 2" BARLOW.  LENSES MAY TOUCH UNLESS BARREL EXTENSION IS ADDED TO EYEPIECE BARREL
Using advanced computer design, combinations of low dispersion and high refractive index optical glasses, and durable multilayer deposition coatings, Explore Scientific 100° Series™ hyper-wide field eyepieces are optimized to produce high contrast, high resolution, and superior flat field characteristics, and yes they are indeed ruggedized and waterproof to withstand the outdoor environment.
The visual effect of these eyepieces with their long eye-relief and their 100° apparent field is an extreme full-immersion experience. You have to try it understand the visual impact that these eyepieces produce.
designers. Wright H. Scidmore [1] patented important ultra-wide angle eyepiece designs (one with long eye-relief) in the ‘60s for the U.S. government. His influence can be seen in many eyepiece designs on the market today with eyepieces of 68 to 80 degrees apparent field and more. Carl Zeiss [2] made eyepieces of 110 and 120 degrees apparent field for use in U-boat periscopes before World War II. These are but two notable designers who developed ultra-wide field eyepieces over the decades.
Years later such eyepiece designs transformed the visual experience for amateur astronomers, as they started using military surplus cannon sight eyepieces on their backyard telescopes. Al Nagler with his company Tele Vue introduced his Nagler 82 Degree eyepieces[3] (and later introduced the 100 degree Ethos eyepieces), and then other commercial telescope companies such as  Meade Instruments, Pentax, Celestron, and others made ultra-wide field eyepieces specifically for use in amateur telescopes. Since extreme performance eyepieces are expensive to make, they come with a relatively high price tag over standard eyepieces.

After announcing Explore Scientific’s line of telescopes at the Astronomical League Conference in the summer of 2008, we decided to focus on extreme performance, ultra-wide angle eyepiece designs as well. We wanted to offer ultra-wide angle designs in popular formats at lower prices. Now more astronomers could experience the benefits of the amazing panoramic views these eyepieces provide.
The development of the Explore Scientific 14mm 100° Series ARGON-Purged Waterproof™ Eyepiece was a collaborative effort of astronomers and engineers who tested our prototypes again and again, in the field and in the factory to make refinements to produce the final production eyepiece.
Like all Explore Scientific eyepieces, the lens elements of the 100° eyepiece are meticulously cleaned and aligned before being installed in their precision machined lens barrels.

Each lens and lens grouping have EMD™ (Enhanced Multilayer Deposition) Coatings and are edge-blackened to eliminate light scatter and maintain image contrast.

Contrast is further enhanced with baffles that mask and deflect unwanted stray light.
These eyepieces with their huge apparent field of view not only gave the observer a panoramic visual experience, but they relax the eye so the observer could pay attention to subtle details for extended periods. These ultra-wide angle eyepieces played a critical role in the military for aiming at targets, and their long eye-relief counterparts helped reduce eye injury from recoil.
Each 100° Series ARGON-Purged Waterproof eyepiece is internally sealed and purged with inert, dry ARGON gas to prevent internal fogging, to halt the intrusion of fine particulates and fungus, and to maximize the life of the internal coatings.

To make sure, every 100° eyepiece is tested by submerging them down to 1 meter of water for 30 minutes.
Developing our new eyepieces we wanted to take a fresh perspective and address several points. Our goal was to produce an ultra-wide angle design that provides pride of ownership at a great value:

Focus on Value - We invite direct comparison to any eyepieces on the market in their category.

Protection from the Outdoors - By making the eyepiece body ARGON-purged and waterproof eyepiece internal elements will remain as pristine as the day they were assembled. The sealed, dry environment is impervious to internal fogging and contaminants such as fungus growing in between the lens elements. Our waterproof eyepiece is easier to clean, and there is no risk of cleaning solution migrating from the top of the lens and seeping around edges to be trapped in between elements. To insure a perfect seal we test every eyepiece in one meter of water for 30 minutes.

Creating an Identity - We look at purchasing fine optical equipment as an investment, and it should be treated as such. With a unique serial number on each eyepiece we can track when a product was made, and the owner can document their equipment for insurance and warranty purposes.

Providing Peace of Mind - Explore Scientific stands behind our products with the free Explore STAR Transferrable Extended Life of the Product Warranty upon registration of the product. Want to trade or sell your eyepiece? You’ll get more value if its remaining warranty can be transferred to the new owner.
All Explore Scientific telescopes and telescope accessories are covered under our standard U.S.A. One Year Limited Warranty against defects with proof of purchase, but you can extend this limited warranty to Explore STAR by simply filling out the product registration and submit it in within 60 days.

This program is also available to the person who receives your gift of an Explore Scientific telescope. You don't need to give them the purchase receipt, just remind them to fill out the registration and submit it, and we'll take care of the rest.
All Explore Scientific telescopes and telescope accessories are covered under our standard U.S.A. One Year Limited Warranty against defects with proof of purchase, but you can extend this limited warranty to the Explore STAR Transferrable Extended Life of the Product Warranty by simply filling out the product registration and submitting it in within 60 days.

This program is also available to the person who receives your gift of an Explore Scientific eyepiece. You don't need to give them the purchase receipt, just remind them to fill out the registration, and we'll take care of the rest.



[1] Ref: W.H. Scidmore, Wide-angle eyepiece, USP 3390935 (1965), and USP 3384434 (1968)

[2] Ref: A New Telescope Eyepiece with Extremely Large Field of View by Horst Kohler, Oberkochen from Optik, Journal for Light and Electron Optics Special Reprint, Optik 17 (1960), pp500-509

[3] Ref: The eyepiece that changed observing, Astronomy Magazine (Dec, 2005)