{"product_id":"explore-scientific-epwp7230ed-01","title":"Explore Scientific 72° ED Series 30mm Waterproof Eyepiece","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e30mm Focal Length\u003c\/li\u003e\n\u003cli\u003e72° Apparent Field of View\u003c\/li\u003e\n\u003cli\u003e2-inch Barrel Diameter\u003c\/li\u003e\n\u003cli\u003eExtra-Low Dispersion (ED) Glass\u003c\/li\u003e\n\u003cli\u003eWaterproof and Gas-Purged Construction\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 Series 30mm Waterproof Eyepiece\u003c\/h2\u003e\n\u003cp\u003eThe Explore Scientific 72° ED 30mm eyepiece leverages a 2-inch barrel to deliver an expansive 72° apparent field of view at a low-power 30mm focal length. This combination is engineered to produce the widest possible true field for sweeping large star fields and framing entire deep-sky objects that are too large for higher-magnification eyepieces.\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\u003eA 72° Field Corrected with ED Glass\u003c\/h3\u003e\n\u003cp\u003eThe eyepiece's 72° apparent field creates a significant immersive effect, removing the sense of looking through a narrow tube. To maintain sharpness across this wide view, the optical design incorporates Extra-Low Dispersion (ED) glass. This high-grade material minimizes chromatic aberration, ensuring stars remain tight points of light and bright objects like Jupiter or the lunar limb are free of distracting color fringing, even at 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\u003eThe 30mm Low-Power, Waterproof Design\u003c\/h3\u003e\n\u003cp\u003eWith its 30mm focal length, this eyepiece provides very low magnification, making it ideal for locating objects and observing large-scale structures like the North American Nebula (NGC 7000) or the full extent of the Andromeda Galaxy (M31). The fully waterproof and gas-purged body prevents internal fogging and protects the coatings from dew, ensuring reliability during long nights in humid conditions. The design also incorporates long eye relief for comfortable viewing, even with eyeglasses.\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° 30mm vs. a Standard 32mm Plössl\u003c\/h3\u003e\n\u003cp\u003eWhile a standard 32mm Plössl is a reliable low-power eyepiece, its view is constrained by a narrower 50-52° apparent field. The Explore Scientific 72° ED 30mm offers a distinct advantage for wide-field observing.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eField of View:\u003c\/strong\u003e The 72° field of the Explore Scientific eyepiece provides a significantly larger and more immersive window into the sky compared to the Plössl's restricted view at a similar magnification.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOptical Correction:\u003c\/strong\u003e The inclusion of ED glass gives the 72° eyepiece an edge in controlling chromatic aberration, resulting in higher contrast and sharper stars across the field.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBuild:\u003c\/strong\u003e A standard Plössl is rarely waterproof. The sealed, gas-purged construction of the 72° ED 30mm makes it a far more robust choice for observers who frequently deal with dew.\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\"\u003eHow does the Explore Scientific 72° 30mm eyepiece perform in an f\/10 SCT on the Andromeda Galaxy (M31)?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThis eyepiece is an excellent match for an f\/10 SCT. It will provide low magnification that allows you to frame the entire core and spiral arms of the Andromeda Galaxy (M31) in a single field of view, something impossible with standard, higher-power eyepieces. The ED glass ensures the dense star field remains sharp across the entire 72° view.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the 72° ED 30mm eyepiece a good choice for my fast f\/4.5 Dobsonian?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eIt can be, but there is a trade-off. In an f\/4.5 telescope, this 30mm eyepiece produces a very large 6.7mm exit pupil. While this delivers a bright image, it may be larger than your eye's pupil, causing some light loss and potentially revealing the shadow of the telescope's secondary mirror. However, for sweeping the Milky Way from a dark site, the bright, wide field can be spectacular.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does \"ED Glass\" do for the view in the 72° 30mm eyepiece?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003e\u003cstrong\u003eExtra-Low Dispersion (ED) glass\u003c\/strong\u003e is a premium optical glass that corrects for chromatic aberration, also known as \"false color.\" This means it focuses all colors of light to the same point, resulting in sharper, higher-contrast images. You'll notice this as tighter stars and a lack of purple or green fringing around bright objects like planets and bright stars.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill I need filters with the Explore Scientific 72° 30mm eyepiece?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe 2-inch barrel is threaded to accept standard 2\" astronomy filters. Because this eyepiece produces a low magnification and bright image, it pairs exceptionally well with nebula filters like a UHC or O-III. These filters will darken the sky background and dramatically increase the contrast on large emission nebulae like the Veil Nebula or the Lagoon Nebula (M8).\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the waterproof feature of the 72° ED 30mm eyepiece benefit my observing sessions?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe waterproof, gas-purged construction prevents moisture from getting inside the eyepiece on dewy nights. This stops internal lens fogging, which can ruin a view and is difficult to clean. It also protects the delicate internal coatings from moisture damage and fungus, ensuring a longer lifespan for the eyepiece.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the main advantage of the 72° field over a standard Plössl?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe primary advantage is immersion. A 72° apparent field of view is wide enough to fill your eye's perception, creating a \"spacewalk\" effect where the eyepiece body seems to disappear. This makes observing large open clusters like the Pleiades (M45) or scanning the Milky Way a much more engaging experience than the more constrained view of a typical 50° Plössl.\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 colspan=\"2\" style=\"text-align:center;\"\u003eNo specifications available.\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\"\u003eNo contents available.\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":52909341802781,"sku":"ES-EPWP7230ED-01","price":560.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/ExploreScientific-72-ED-Series-30mm-Waterproof-Eyepiece-1_f8c58428-3140-4bb6-82d0-d477f514d167.jpg?v=1789061334","url":"https:\/\/davidastro.com\/products\/explore-scientific-epwp7230ed-01","provider":"David Astro","version":"1.0","type":"link"}