{"product_id":"televue-plossl-20mm-50-eyepiece","title":"TeleVue Plössl 20mm 50° Eyepiece - 1.25\"","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e20mm Focal Length\u003c\/li\u003e\n\u003cli\u003e50° Apparent Field of View\u003c\/li\u003e\n\u003cli\u003e1.25\" Diameter Barrel\u003c\/li\u003e\n\u003cli\u003e15mm Eye Relief\u003c\/li\u003e\n\u003cli\u003e17.1mm Field Stop\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\u003eTeleVue Plössl 20mm 50° Eyepiece - 1.25\"\u003c\/h2\u003e\n\u003cp\u003eThe TeleVue Plössl 20mm 50° Eyepiece is a four-element symmetric design engineered to provide high-contrast lunar and planetary images in 1.25-inch format focusers. This focal length serves as a medium-power optic in most amateur telescopes, balancing magnification and exit pupil for deep-sky and solar system targets. Every air-to-glass surface features proprietary multi-coatings to reduce internal reflections and maximize transmission.\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\u003e17.1mm Field Stop and Framing Performance\u003c\/h3\u003e\n\u003cp\u003eThe 17.1mm field stop produces a 50° apparent field of view (AFOV) that remains sharp to the edge when used in telescopes with slower focal ratios. In an 8-inch f\/10 Schmidt-Cassegrain, this eyepiece yields 100x magnification and a 0.5° true field, sufficient to frame the full disc of the Moon. This field diameter is physically constrained by the symmetric Plössl geometry to ensure stars do not suffer from significant edge-of-field aberrations.\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\u003eOptical Baffling and Contrast for Planetary Detail\u003c\/h3\u003e\n\u003cp\u003eTeleVue utilizes high-index glass and blackened lens edges to minimize stray light scattering when observing bright targets like Jupiter or Venus. The simplified four-element layout has fewer air-to-glass surfaces than ultra-wide designs, which can reduce the probability of ghosting during lunar observations. This design provides a neutral color rendition, preserving the natural chromatic appearance of double stars like Albireo (Beta Cygni).\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\u003e15mm Eye Relief and Mechanical Compatibility\u003c\/h3\u003e\n\u003cp\u003eWith 15mm of eye relief, the TeleVue Plössl 20mm allows most observers to see the entire 50° field, though eyeglass wearers with thick frames may find the distance tight. The 1.25-inch barrel is threaded for standard filters and features a safety undercut to prevent the eyepiece from slipping out of the diagonal or focuser. At a weight of 3.8 oz, this optic is significantly lighter than wide-angle alternatives, reducing the need for mount rebalancing.\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\u003eTeleVue Plössl 20mm vs. 19mm Panoptic: Field vs. Eye Relief\u003c\/h3\u003e\n\u003cp\u003eWhile the 19mm Panoptic offers a wider 68° apparent field, the TeleVue Plössl 20mm utilizes a simpler optical path that some observers prefer for critical on-axis planetary work. The 20mm Plössl is more compact and budget-accessible but offers slightly less eye relief (15mm) compared to the 19mm Panoptic (13mm, though with a different eye guard style). Choose the Plössl for high center-field contrast in long focal length refractors or SCTs.\u003c\/p\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\"\u003eIs the TeleVue Plössl 20mm suitable for use with a Barlow lens?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, the 20mm Plössl pairs well with the TeleVue 2x or 3x Barlow. When used with a 2x Barlow, it functions as a 10mm eyepiece with high contrast, while maintaining its original 15mm eye relief for comfortable high-power viewing.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the TeleVue Plössl 20mm with a Dioptrx corrector?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, the 20mm Plössl is not directly compatible with the TeleVue Dioptrx astigmatism corrector. The Dioptrx requires specific eyeguard housing sizes found on longer focal length Plössls (32mm and 55mm) or Radian, Delos, and Nagler series eyepieces.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the TeleVue Plössl 20mm work well in fast f\/4 or f\/5 Newtonian telescopes?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWhile sharp on-axis, simple Plössl designs show astigmatism near the edge of the field in telescopes faster than f\/5. For pinpoint stars to the edge in fast Dobsonians, consider the TeleVue Delos or DeLite series, though the 20mm Plössl remains an excellent center-field performer.\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\u003eModel #\u003c\/td\u003e\n\u003ctd\u003eEAP-20.0\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Length\u003c\/td\u003e\n\u003ctd\u003e20 mm\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\u003eApparent Field of View\u003c\/td\u003e\n\u003ctd\u003e50°\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEye Relief\u003c\/td\u003e\n\u003ctd\u003e15 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eField Stop Diameter\u003c\/td\u003e\n\u003ctd\u003e17.1 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e3.8 oz (108 g)\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\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/TeleVue-Plossl-20mm-Eyepiece-1.jpg?v=1775788667\" alt=\"TeleVue 20mm Plössl\" class=\"DAV-img-box\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDust Cap (Top)\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/TeleVue-Dust-Cap-Top.jpg?v=1775788926\" alt=\"TeleVue 20mm Plössl Dust Cap Top\" class=\"DAV-img-box\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDust Cap (Top)\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/TeleVue-1_25inch-Dustcap.jpg?v=1774403145\" alt=\"TeleVue 20mm Plössl Dust Cap Bottom\" class=\"DAV-img-box\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDust Cap (Bottom)\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\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/TeleVue-20mm-Plossl-Eyepiece-Manual.pdf?v=1775788607\" target=\"_blank\"\u003e\u003csvg class=\"DAV-img-box\" viewbox=\"0 0 512 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath d=\"M0 64C0 28.7 28.7 0 64 0L224 0l0 128c0 17.7 14.3 32 32 32l128 0 0 144-208 0c-35.3 0-64 28.7-64 64l0 144-48 0c-35.3 0-64-28.7-64-64L0 64zm384 64l-128 0L256 0 384 128zM176 352l32 0c30.9 0 56 25.1 56 56s-25.1 56-56 56l-16 0 0 32c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-48 0-80c0-8.8 7.2-16 16-16zm32 80c13.3 0 24-10.7 24-24s-10.7-24-24-24l-16 0 0 48 16 0zm96-80l32 0c26.5 0 48 21.5 48 48l0 64c0 26.5-21.5 48-48 48l-32 0c-8.8 0-16-7.2-16-16l0-128c0-8.8 7.2-16 16-16zm32 128c8.8 0 16-7.2 16-16l0-64c0-8.8-7.2-16-16-16l-16 0 0 96 16 0zm80-112c0-8.8 7.2-16 16-16l48 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 32 32 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 48c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-64 0-64z\" fill=\"#0047a7\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Manual\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/davidastro.com\/pages\/televue-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eTeleVue 5-Year Limited Warranty for Telescopes and Accessories\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"TeleVue","offers":[{"title":"Default Title","offer_id":51134646386973,"sku":"TV-EAP-20.0","price":138.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/TeleVue-Plossl-20mm-Eyepiece-1.jpg?v=1775788667","url":"https:\/\/davidastro.com\/en-us\/products\/televue-plossl-20mm-50-eyepiece","provider":"David Astro","version":"1.0","type":"link"}