{"product_id":"tele-vue-delos-4-5mm-72-degree-eyepiece","title":"Tele Vue Delos 4.5mm 72° Eyepiece - 1.25\"","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eFocal Length: 4.5mm\u003c\/li\u003e\n\u003cli\u003eApparent Field of View: 72°\u003c\/li\u003e\n\u003cli\u003eBarrel Size: 1.25\"\u003c\/li\u003e\n\u003cli\u003eEye Relief: 20mm\u003c\/li\u003e\n\u003cli\u003eField Stop Diameter: 5.9mm\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\u003eHigh-Power Views, Without the High-Power Strain\u003c\/h2\u003e\n\u003cp\u003eThe Tele Vue Delos 4.5mm 72° Eyepiece delivers high-magnification planetary, lunar, and double-star views with a level of comfort that changes the game for serious observers. It combines a sharp, high-contrast optical system with a generous 20mm of eye relief, solving the age-old problem of eye strain during detailed, high-power observation. The result is a forgiving, immersive experience that encourages longer, more productive sessions at the telescope.\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 Pure, High-Contrast Optical Path\u003c\/h3\u003e\n\u003cp\u003eThe Delos optical design uses high-index glasses and continuous multi-coatings on every air-to-glass surface to maximize light throughput and suppress internal reflections. This engineering delivers a neutral, high-fidelity image with dark sky backgrounds, allowing subtle planetary details and faint stellar companions to become visible. The color rendition is true to life, without the warm or cool tint introduced by lesser eyepieces.\u003c\/p\u003e\n\u003cp\u003eOn a target like Jupiter, this translates to seeing delicate festoons and small ovals within the cloud belts, not just the primary bands themselves. The high contrast makes it easier to discern the Cassini Division in Saturn's rings, even on nights of average seeing. This is not just a sharp eyepiece; it is a transparent window to the target.\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 Freedom of 20mm Eye Relief\u003c\/h3\u003e\n\u003cp\u003eHigh-power eyepieces are traditionally associated with tight, uncomfortable eye relief, forcing you to press your eye against the lens. The Delos 4.5mm breaks this rule by providing a constant 20mm of eye relief, a specification typically found only in low-power eyepieces. This design choice provides a relaxed, spacious view, which is a significant advantage for eyeglass wearers who can now see the entire field of view without removing their glasses.\u003c\/p\u003e\n\u003cp\u003eThis long eye relief also benefits observers who do not wear glasses. It eliminates the feeling of being \"crowded\" by the eyepiece, reducing fatigue and making it easier to hold a steady view for extended periods. This is particularly valuable when studying fine details that require patience and concentration, such as tracking shadow transits across a planetary disk.\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 Lockable Eyeguard and Consistent Performance\u003c\/h3\u003e\n\u003cp\u003eTo manage the long eye relief and prevent blackouts, the Delos features an innovative adjustable and lockable eyeguard. By simply twisting the housing, you can raise the soft rubber eyeguard to the exact height that positions your eye perfectly, then lock it in place. This ensures you get the same comfortable, full-field view every time you come to the eyepiece, without needing to hunt for the right position.\u003c\/p\u003e\n\u003cp\u003eThis mechanism is a practical workflow improvement. It saves time and frustration, especially when sharing the telescope with others or when switching between eyepieces. Once you find your perfect setting, it remains fixed, making the eyepiece feel like a custom-fit instrument for your eye.\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 Immersive 72° Apparent Field\u003c\/h3\u003e\n\u003cp\u003eThe 72° apparent field of view strikes a deliberate balance between a wide, immersive experience and optical purity. While not as expansive as an 82° or 100° field, the 72° frame is wide enough to feel like a \"porthole\" view, yet it allows the optical design to maintain exceptional sharpness and contrast right to the very edge of the field stop. There is no pincushion or barrel distortion, so straight lines remain straight as you pan across the lunar terminator.\u003c\/p\u003e\n\u003cp\u003eThis well-corrected field is a significant asset for planetary and lunar observers. When tracking a planet at high power, the object drifts across a consistently sharp field, giving you more time to study details before needing to adjust the mount. On a small planetary nebula like the Ring Nebula (M57), the 4.5mm Delos in a long-focus refractor will frame the nebula beautifully against a dark background, with surrounding field stars remaining perfect points.\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\u003eSuperior Contrast from Barrel to Baffle\u003c\/h3\u003e\n\u003cp\u003eTele Vue's commitment to contrast extends beyond the optics. The 1.25\" barrel is machined with a tapered undercut on the barrel, which provides a more secure connection than simple safety grooves and prevents the eyepiece from accidentally falling out of the focuser. Internally, the eyepiece features flat-blackened lens edges and baffles that are strategically placed to trap any stray light that might otherwise reduce contrast and wash out faint details.\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\u003eObserve Without Glasses with Dioptrx Compatibility\u003c\/h3\u003e\n\u003cp\u003eFor observers with astigmatism, the Delos series is fully compatible with Tele Vue's Dioptrx correctors. The top of the eyepiece is threaded to accept a Dioptrx unit, which replaces the need for eyeglasses at the telescope. This creates a direct optical path from the eyepiece to your eye, eliminating the extra reflections and potential misalignments of wearing glasses and resulting in a sharper, higher-contrast 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\u003eA Note on Seeing Conditions\u003c\/h3\u003e\n\u003cp\u003eThe Delos 4.5mm is a high-magnification instrument, and its performance is directly tied to the stability of the Earth's atmosphere. While its optical quality is superb, it cannot see through poor \"seeing.\" On nights of atmospheric turbulence, the view may appear soft or shimmering. However, its forgiving eye relief and high contrast mean that during fleeting moments of steady air, the details that snap into focus will be rendered with exceptional clarity.\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\u003eChoosing Your High-Power Eyepiece: Delos vs. Nagler\u003c\/h3\u003e\n\u003cp\u003eWhen considering a high-power eyepiece, many observers weigh the Delos against the Nagler series. The choice comes down to your primary observing style.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eTele Vue Delos 4.5mm:\u003c\/strong\u003e You prioritize comfort, eye relief, and the highest possible contrast for detailed planetary and double-star work. You wear glasses or simply want a more relaxed, less critical viewing experience without sacrificing optical sharpness.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTele Vue Nagler Type 6 5mm:\u003c\/strong\u003e You want the most immersive, \"spacewalk\" experience possible and are willing to trade some eye relief for a wider 82° field of view. This is often the choice for observers who want to frame objects within a larger context, such as globular clusters or small nebulae.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Delos 4.5mm good for a beginner?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWhile it is a premium eyepiece, its long eye relief and forgiving nature make it much easier to use than traditional high-power eyepieces. For a beginner with a quality telescope who wants to specialize in lunar and planetary observing, it can be an excellent long-term investment.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill this eyepiece work well with my f\/5 Dobsonian?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, the Delos line is well-corrected for fast telescopes. In an f\/5 system, the 4.5mm Delos will deliver sharp stars across the field. You will also need a coma corrector like the Tele Vue Paracorr Type 2 to achieve the best performance.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the Delos 4.5mm compare to a 4mm planetary eyepiece?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Delos 4.5mm offers a significantly wider 72° apparent field and much more comfortable eye relief than typical 4mm Orthoscopic or Plössl eyepieces. While those designs are very sharp, the Delos provides a more immersive and comfortable experience for extended viewing sessions.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy would I choose the 4.5mm Delos over the 3.5mm Delos?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe 4.5mm provides lower magnification, which is usable on more nights of average atmospheric seeing. The 3.5mm Delos requires very stable seeing conditions to perform at its best and is a more specialized tool for nights of exceptional atmospheric stability.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the locking eyeguard for?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe long 20mm eye relief means your eye needs to be positioned at a specific distance from the lens to see the whole field without blackouts. The locking eyeguard lets you set this position perfectly for your eye (with or without glasses) and lock it there, so you get a perfect view every time.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use Dioptrx with the Delos 4.5mm eyepiece?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, the Delos line is designed to be compatible with Tele Vue's Dioptrx astigmatism correctors. This allows you to observe without your glasses and achieve a perfectly sharp focus.\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\u003eEDL-04.5\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Length\u003c\/td\u003e\n\u003ctd\u003e4.5mm\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 (AFOV)\u003c\/td\u003e\n\u003ctd\u003e72°\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEye Relief\u003c\/td\u003e\n\u003ctd\u003e20mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eField Stop Diameter\u003c\/td\u003e\n\u003ctd\u003e5.9mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCoatings\u003c\/td\u003e\n\u003ctd\u003eFully Multi-Coated\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e7.2 oz (0.45 lbs \/ 204 g)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDimensions\u003c\/td\u003e\n\u003ctd\u003e1.9\" D x 3.6\" H (48mm x 91mm)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDioptrx Compatible\u003c\/td\u003e\n\u003ctd\u003eYes\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\"\u003eTele Vue Delos 4.5mm Eyepiece\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\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eTop Dust Cap\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\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eBottom Dust Cap\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\/Tele_Vue_Delos_4.5mm_Eyepiece_Manual.pdf\" 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\n\u003ca href=\"https:\/\/davidastro.com\/pages\/tele-vue-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eTele Vue 5-Year Limited Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"TeleVue","offers":[{"title":"Default Title","offer_id":51223879024925,"sku":"TV-EDL-04.5","price":438.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Tele_Vue_Delos_4.5mm_Eyepiece_1.jpg?v=1777515020","url":"https:\/\/davidastro.com\/fr-eu\/products\/tele-vue-delos-4-5mm-72-degree-eyepiece","provider":"David Astro","version":"1.0","type":"link"}