{"product_id":"explore-scientific-epwp7285ed-01","title":"Explore Scientific 72° ED 8.5mm Waterproof Eyepiece","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e8.5mm Focal Length\u003c\/li\u003e\n\u003cli\u003e72° Apparent Field of View\u003c\/li\u003e\n\u003cli\u003eExtra-Low Dispersion (ED) Glass\u003c\/li\u003e\n\u003cli\u003e1.25\" Barrel Diameter\u003c\/li\u003e\n\u003cli\u003eWaterproof and Gas-Purged\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eDownloads\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eExplore Scientific 72° ED 8.5mm Waterproof Eyepiece\u003c\/h2\u003e\n\u003cp\u003eThe Explore Scientific 72° ED Series 8.5mm Waterproof Eyepiece delivers a wide 72° apparent field of view in a versatile 8.5mm focal length perfect for high-contrast planetary and deep-sky observation. Its 1.25-inch barrel design incorporates Extra-Low Dispersion (ED) glass to virtually eliminate chromatic aberration, ensuring sharp, color-pure views from the center to the edge of the field.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eAn 8.5mm Focal Length with ED Glass Correction\u003c\/h3\u003e\n\u003cp\u003eThe 8.5mm focal length provides significant magnification for resolving fine details on planetary surfaces, splitting tight double stars, and examining the cores of compact deep-sky objects. The inclusion of ED glass is critical at these magnifications, as it corrects for chromatic aberration—the color fringing seen around high-contrast targets like the limb of Jupiter or bright stars. This results in a cleaner, higher-contrast image where subtle details are not washed out by false color.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eThe 72° Apparent Field of View Advantage\u003c\/h3\u003e\n\u003cp\u003eWith a 72° apparent field of view, this eyepiece offers an immersive, wide-window experience that makes observing more comfortable and engaging than standard 50° designs. For users with non-tracking mounts like Dobsonians, the wider field means celestial objects stay in view longer before needing adjustment. This generous field is ideal for framing smaller open clusters and planetary nebulae within their stellar context, providing a more satisfying and complete view.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eWaterproof Design for Field Reliability\u003c\/h3\u003e\n\u003cp\u003eDesigned for real-world observing conditions, the eyepiece is fully waterproof and argon-purged. This sealed construction prevents internal fogging during nights with heavy dew and protects the internal optics from dust and moisture. This not only ensures reliable views regardless of the weather but also makes the eyepiece much easier to clean without risk of moisture seeping into the housing.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eExplore Scientific 72° ED 8.5mm vs. a Tele Vue 8mm Plössl\u003c\/h3\u003e\n\u003cp\u003eWhen choosing a premium high-magnification eyepiece, a benchmark like the Tele Vue 8mm Plössl is known for its exceptional sharpness and contrast in a compact form factor. However, the Explore Scientific 72° ED 8.5mm eyepiece presents a different set of advantages for the observer.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eWider Apparent Field:\u003c\/strong\u003e The most significant difference is the 72° field of the Explore Scientific eyepiece compared to the 50° field of the Plössl. This provides a much more expansive and immersive viewing experience.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eED Glass Element:\u003c\/strong\u003e The ED glass in the 72° Series specifically targets and minimizes chromatic aberration, offering superior color correction on bright objects.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSealed Construction:\u003c\/strong\u003e The waterproof and argon-purged body of the Explore Scientific eyepiece offers greater durability and resistance to dew, a feature not present in the standard Plössl design.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat objects are best for the Explore Scientific 72° ED 8.5mm eyepiece?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe 8.5mm focal length is excellent for high-magnification views of bright objects. It excels at resolving cloud bands on \u003cstrong\u003eJupiter\u003c\/strong\u003e, the Cassini Division in \u003cstrong\u003eSaturn's rings\u003c\/strong\u003e, and fine crater details on the \u003cstrong\u003eMoon\u003c\/strong\u003e. It's also ideal for smaller, bright deep-sky objects like the Ring Nebula (M57) and globular clusters like the Hercules Cluster (M13).\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the 72° field of view on the ED 8.5mm eyepiece help with a Dobsonian telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eFor non-tracking telescopes like a \u003cstrong\u003eDobsonian\u003c\/strong\u003e, a wider field of view is a major asset. The 72° field allows an object to drift across the eyepiece for a longer period before you need to nudge the telescope, making for more relaxed and continuous observation, especially at high power.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the Explore Scientific 72° ED 8.5mm eyepiece work for observers who wear glasses?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, this eyepiece is designed with \u003cstrong\u003elong eye relief\u003c\/strong\u003e. This allows eyeglass wearers to see the entire 72° field of view comfortably without having to press their glasses against the lens, which is often a problem with short eye relief eyepieces.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the benefit of ED glass in the 8.5mm eyepiece when viewing Jupiter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWhen viewing a bright planet like \u003cstrong\u003eJupiter\u003c\/strong\u003e, lesser eyepieces can show a purple or blue fringe of false color around the planet's edge. The \u003cstrong\u003eExtra-Low Dispersion (ED) glass\u003c\/strong\u003e in the Explore Scientific 72° ED 8.5mm corrects this, resulting in a sharp, high-contrast view with true-to-life colors, making it easier to see subtle details in the cloud bands.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy is a waterproof eyepiece like the Explore Scientific 72° ED 8.5mm useful?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eA waterproof, gas-purged design prevents dew from forming on internal lens surfaces, a common problem during long nights in humid climates. It also keeps dust and fungus out of the optical path, ensuring the eyepiece performs like new for years and can be cleaned without fear of introducing moisture inside.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the 8.5mm focal length on the Explore Scientific 72° ED eyepiece compare to a 25mm eyepiece?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAn 8.5mm eyepiece provides much higher magnification than a 25mm eyepiece. In a telescope with a 1000mm focal length, the 8.5mm would yield approximately 118x magnification, while a 25mm would provide 40x. The 8.5mm is for detailed, close-up views, whereas the 25mm is for wide-field scanning and finding objects.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Length\u003c\/td\u003e\n\u003ctd\u003e8.5mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eApparent Field of View\u003c\/td\u003e\n\u003ctd\u003e72°\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBarrel Size\u003c\/td\u003e\n\u003ctd\u003e1.25\"\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003eContains Extra-Low Dispersion (ED) Glass\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eConstruction\u003c\/td\u003e\n\u003ctd\u003eWaterproof, Argon-Purged\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEye Relief\u003c\/td\u003e\n\u003ctd\u003eLong (Eyeglass Friendly)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003e72° ED Series 8.5mm Waterproof Eyepiece\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/explore-scientific-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eExplore Scientific Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Explore Scientific","offers":[{"title":"Default Title","offer_id":52909345571101,"sku":"ES-EPWP7285ED-01","price":420.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/ExploreScientific-72-ED-Series-8-5mm-Waterproof-Eyepiece-1_0b22e52f-8524-4dc9-89f6-13e89c5c20ec.jpg?v=1789061366","url":"https:\/\/davidastro.com\/fr\/products\/explore-scientific-epwp7285ed-01","provider":"David Astro","version":"1.0","type":"link"}