Using the latest advanced computer design, a combination of low dispersion and high refractive index optical glasses, and durable multilayer high transmission coatings, Explore Scientific 68° Series Argon-Purged Waterproof extreme wide field eyepieces are optimized to produce very high contrast, high resolution, and superior flat field optical characteristics. The visual effect of these eyepieces with their long eye-relief and their 68° apparent field is truly a full-immersion experience. The 68° Series eyepieces come with a removeable and foldable soft silicone rubber eyecup for the comfort of the observer, and as experienced astronomers know, eye comfort is critical when trying to observe at the visual limits of the telescope.
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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 by 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 prevents 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 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.
Our delivery charge for most of the UK is £3.95. All orders are shipped promptly, lower value items are sent Royal Mail 1st class and higher value or larger goods are shipped via reputable courier. All goods are shipped fully insured with FEDEX, UPS, DPD, DHL and Royal Mail, we do not use budget courier services, we can only ship to UK mainland addresses and are not able to ship to forwarding agents or PO boxes.
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We ship each business day, orders received before lunch are normally shipped that business day. We also direct ship from our UK suppliers, this means we have access to thousands of products that can ship fast to our customers.
Deliveries to UK mainland addresses are all shipped with fully insured premium services for £3.95, *some exceptions apply including many AB, FK, HS, IV, KA, KW, PA, PH, ZE postcodes. We will quote delivery charges to these areas where applicable prior to shipping (this does not normally affect lower value items shipped by Royal Mail).
You must inform us within one working day if the goods are lost or damaged in transit so that we can make a prompt claim against the delivery company and correct the problem. Please ensure all address details are accurate, we cannot be responsible for failed deliveries or losses arising from incorrect delivery addresses.
You agree that proof of delivery supplied by our delivery company is sufficient evidence to establish that goods have been received.
If your product is sent by Courier they will attempt delivery twice and a signature will be required. If they are unable to deliver because you are not available and after 5 days you have not contacted them to re-arrange. the goods will be returned to us and the return delivery costs may be charged to you