Explore Scientific - 100° Series 9mm and 20mm Nitrogen Purged Waterproof Eyepieces

Specifications

Focal Length: 9mm and 20mm
AFOV: 100 degrees
Nitrogen-Purged and Waterproof: Internally sealed and purged with inert, dry nitrogen 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, each eyepiece is tested by submerging each unit in 1 meter of water for 30 minutes.
Coatings: All lens-to-air surfaces are fully multi-coated
Eyecups: Soft rubber folding style; Replaceable
Weight: 2 lbs
Quality Control: Every Explore Scientific eyepiece is checked again and again both in the manufacturing facility in China and again in our facility in California to insure that each eyepiece will perform to its utmost.

Inspiration for ultra-wide field eyepiece designs came from several designers. Wright H. Scidmore 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 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.

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.

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. Later, commercial telescope companies such as Televue [3], Meade Instruments, Pentax, Celestron, and others made ultra-wide field eyepieces specifically for use in amateur telescopes. Since these 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 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 panoramic views and would not feel too nervous about sharing the eyepiece during public outreach events, where sometimes an eyepiece becomes mishandled. It is sharing the amazing panoramic viewing experience with the public that is most important to us, was we feel that it will compel more people to become interested in astronomy and in science in general.

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 nitrogen-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 a free 5 Year Transferrable Limited 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.