{"title":"Explore Scientific 52° Series Eyepieces","description":"\u003cp\u003eExplore Scientific 52° Series eyepieces are compact, waterproof and argon-purged eyepieces with a moderate apparent field, close to a classic Plössl but in a sealed body. The 1.25\" range runs from 3mm, 4.5mm and 6.5mm for the Moon and planets to 10mm, 15mm, 20mm, 25mm and 30mm, with a 40mm in a 2\" barrel.\u003c\/p\u003e\u003cp\u003eThey make a simple, consistent set for beginners building a first eyepiece kit, and they stay light enough for small telescopes and travel setups.\u003c\/p\u003e","products":[{"product_id":"explore-scientific-52-3mm-waterproof-eyepiece-1-25","title":"Explore Scientific 52° 3mm Waterproof Eyepiece - 1.25\"","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e3mm Focal Length for High-Power Observing\u003c\/li\u003e\n\u003cli\u003e52° Apparent Field of View\u003c\/li\u003e\n\u003cli\u003e1.25\" Barrel Diameter\u003c\/li\u003e\n\u003cli\u003eFully Waterproof and Argon-Purged\u003c\/li\u003e\n\u003cli\u003eEnhanced Multi-Layer Deposition (EMD) Coatings\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 52° 3mm Waterproof Eyepiece - 1.25\"\u003c\/h2\u003e\n\u003cp\u003eThe Explore Scientific 52° 3mm eyepiece is a specialized optical tool designed for high-magnification planetary and double-star observation. Its 3mm focal length delivers extreme power in most telescopes, while the 52° apparent field provides a classic, sharp window for on-axis viewing, all housed in a rugged, waterproof 1.25\" body.\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\u003eHigh-Power Planetary Viewing: The 3mm Focal Length\u003c\/h3\u003e\n\u003cp\u003eWith a 3mm focal length, this eyepiece is built to push your telescope to its magnification limit on nights of steady seeing. In short-focal-length refractors, it provides the high power needed to resolve fine details on Jupiter's cloud bands or Saturn's rings. In larger instruments like Schmidt-Cassegrains or large Dobsonians, it achieves the magnifications required to split challenging double stars and examine the cores of bright globular clusters like M13.\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\u003eContrast-Optimized Optics: 52° Field with EMD Coatings\u003c\/h3\u003e\n\u003cp\u003eThe 52° apparent field of view is a deliberate design choice that prioritizes on-axis sharpness and contrast over an ultra-wide, immersive experience. This focused view is ideal for planetary work, where detecting subtle color variations and low-contrast details is critical. The optical system is fully EMD (Enhanced Multi-Layer Deposition) Coated with edge-blackened lenses to minimize internal reflections and maximize light transmission, ensuring a dark background sky and bright, crisp images.\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\u003eAll-Weather Reliability: Argon-Purged Waterproof Construction\u003c\/h3\u003e\n\u003cp\u003eAn inert argon-gas purge makes the eyepiece completely waterproof, preventing internal fogging when moving from a warm environment to cold outdoor conditions. This hermetic seal also protects the delicate internal coatings from moisture, fungus, and dust, ensuring the eyepiece maintains its optical integrity for years of use. This rugged construction makes it a reliable choice for observers in humid climates or those who frequently encounter dewing conditions.\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\u003eES 52° vs. Wider Field Eyepieces: A Focused Approach\u003c\/h3\u003e\n\u003cp\u003eWhile wider 68°, 82°, or 100° eyepieces offer a breathtaking \"spacewalk\" feeling, they achieve it with more complex optical designs that can sometimes compromise central sharpness and contrast. The Explore Scientific 52° 3mm eyepiece takes a different approach.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eOn-Axis Priority:\u003c\/strong\u003e The simpler optical formula is optimized for the highest possible contrast and resolution at the center of the field, which is exactly where you place a planet or tight double star.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eComfort and Simplicity:\u003c\/strong\u003e The 52° field is comfortable and easy to take in, without the need to pan your eye around to see the edges. It's a classic design for a reason, favored by planetary observers who value optical purity above all else.\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 is the Explore Scientific 3mm 52° eyepiece best for?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Explore Scientific 3mm 52° eyepiece excels at \u003cstrong\u003ehigh-magnification observation\u003c\/strong\u003e of bright, small targets. Its primary uses are for detailed views of planets like Jupiter, Saturn, and Mars, splitting close binary stars, and examining the cores of planetary nebulae and bright globular clusters.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow will the Explore Scientific 3mm 52° perform in my 8\" f\/10 SCT?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eIn a typical 8\" f\/10 Schmidt-Cassegrain Telescope, this 3mm eyepiece will produce extremely high magnification. This level of power is useful only on nights with \u003cstrong\u003every steady atmospheric seeing\u003c\/strong\u003e. Under such conditions, it would be an excellent choice for attempting to resolve the Cassini Division in Saturn's rings all the way around or splitting very tight double stars like Epsilon Lyrae into its four components.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy choose a 52° field of view for the ES 3mm eyepiece instead of a wider one?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe 52° apparent field of view is a deliberate design choice to maximize on-axis contrast and sharpness. For high-power planetary and double star observing, performance at the center of the field is more critical than a wide, immersive view. This design delivers the highest possible image fidelity for these specific targets.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does \"Argon-Purged Waterproof\" mean for the ES 3mm 52° eyepiece?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThis means the eyepiece barrel is sealed and filled with a dry, inert gas (argon). This process offers two key benefits:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003ePrevents Internal Fogging:\u003c\/strong\u003e It stops condensation from forming on internal lens surfaces when you take the eyepiece from a warm house into the cold night air.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProtects Coatings:\u003c\/strong\u003e The seal keeps out moisture and microscopic dust, preventing the growth of fungus and preserving the lens coatings for a longer lifespan.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill I need a Barlow lens with the Explore Scientific 3mm 52° eyepiece?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAlmost certainly not. For the vast majority of telescopes, the 3mm focal length will provide more than enough magnification on its own. Using a Barlow with this eyepiece would likely push the magnification beyond what the telescope's aperture or the atmospheric seeing can support, resulting in a dim and blurry image.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Explore Scientific 3mm 52° eyepiece a good choice for resolving the Trapezium in the Orion Nebula (M42)?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, it is an excellent choice for that specific task. The high power of the 3mm eyepiece will darken the sky background, increasing the contrast between the four main Trapezium stars (A, B, C, and D) and the surrounding nebulosity. On a very steady night, it may also help you glimpse the fainter E and F stars with a moderate-to-large aperture telescope.\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\u003e3mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eApparent Field of View\u003c\/td\u003e\n\u003ctd\u003e52°\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\u003eWaterproof\u003c\/td\u003e\n\u003ctd\u003eYes, Argon-Purged\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCoatings\u003c\/td\u003e\n\u003ctd\u003eEMD (Enhanced Multi-Layer Deposition)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eGTIN\u003c\/td\u003e\n\u003ctd\u003e811803030008\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\"\u003eExplore Scientific 52° 3mm Waterproof Eyepiece - 1.25\"\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\"\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\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\u003cp\u003eNo downloads are available for this product.\u003c\/p\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":44967200129309,"sku":"ES-EPWP5203-01","price":97.99,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Explore-Scientific-3mm-52-deg-Series-Waterproof-Eyepiece-EPWP5203-01-1__92046.1594240349.1280.1280.jpg?v=1684338750"},{"product_id":"explore-scientific-52-10mm-waterproof-eyepiece-1-25","title":"Explore Scientific 52° 10mm Waterproof Eyepiece - 1.25\"","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e10mm Focal Length\u003c\/li\u003e\n\u003cli\u003e52° Apparent Field of View\u003c\/li\u003e\n\u003cli\u003e1.25\" Barrel Diameter\u003c\/li\u003e\n\u003cli\u003eWaterproof, Argon-Purged Construction\u003c\/li\u003e\n\u003cli\u003eFlat-Field Multi-Element Optical Design\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 52° 10mm Waterproof Eyepiece - 1.25\"\u003c\/h2\u003e\n\u003cp\u003eThe Explore Scientific 52° 10mm Waterproof Eyepiece delivers a critical medium-power view through its 1.25\" barrel, providing a sharp 52° apparent field of view. This multi-element ocular is argon-purged to be fully waterproof, ensuring it remains free of internal fogging during dewy nights where simpler eyepieces would fail.\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 10mm Focal Length: Your Go-To for Medium Magnification\u003c\/h3\u003e\n\u003cp\u003eA 10mm eyepiece is a foundational tool in any observer's kit, marking the transition from low-power scanning to detailed observation. It provides enough magnification to resolve detail in brighter deep-sky objects and begin splitting tight double stars, without pushing the limits of atmospheric seeing on most nights.\u003c\/p\u003e\n\u003cp\u003eFor many amateur telescopes, this focal length is ideal for targets that are too dim to withstand very high power. Objects like the Dumbbell Nebula (M27) or the galaxies of the Leo Triplet (M65, M66, NGC 3628) are framed perfectly, revealing structure that would be lost at lower magnification.\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\u003e52° Flat-Field Optics for Superior Contrast\u003c\/h3\u003e\n\u003cp\u003eWith an apparent field of view of 52 degrees, this eyepiece presents a classic, immersive window on the sky. Its advanced flat-field, multi-element design produces excellent contrast, which is crucial for discerning faint details against the sky background. This high-contrast view makes it easier to use averted vision—looking slightly to the side of a target—to detect faint extensions in nebulae or the dim outer stars of a globular cluster.\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\u003e1.25\" Barrel with Argon-Purged Waterproofing\u003c\/h3\u003e\n\u003cp\u003eThe chief advantage of this eyepiece is its sealed, waterproof construction. The optical housing is purged with inert argon gas, which prevents internal condensation from forming when the temperature drops. This means you can move from a warm house to a cold observing site without the eyepiece fogging up from the inside.\u003c\/p\u003e\n\u003cp\u003eThis hermetic seal also protects the internal lens coatings from moisture, fungus, and dust over the long term. The standard 1.25\" barrel ensures compatibility with the vast majority of telescope focusers and diagonal mirrors.\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 10mm 52° vs. a Standard 10mm Plössl\u003c\/h3\u003e\n\u003cp\u003eWhile a standard Plössl is a common entry-level eyepiece, the Explore Scientific 52° 10mm offers distinct advantages for a modest increase in investment.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eStandard Plössl Advantage:\u003c\/strong\u003e A simple 4-element Plössl is often lighter and less expensive.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eExplore Scientific 52° Advantage:\u003c\/strong\u003e The multi-element, flat-field design of the Explore Scientific eyepiece provides sharper stars at the edge of the field, especially in faster telescopes. Its superior contrast and fully waterproof build make it a far more reliable and capable tool for serious deep-sky observing.\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 makes the Explore Scientific 10mm 52° eyepiece waterproof?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe eyepiece is hermetically sealed and purged with \u003cstrong\u003einert argon gas\u003c\/strong\u003e. This process removes internal moisture-laden air, preventing condensation from forming on the internal lens surfaces when the eyepiece gets cold. It also protects the delicate coatings from long-term degradation.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the 52° field of view in this eyepiece compare to a standard Plössl?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe 52° apparent field of view is very similar to that of a classic Plössl design. The key difference is in the optical correction; the Explore Scientific 52° series uses a more advanced \u003cstrong\u003eflat-field design\u003c\/strong\u003e that maintains better star sharpness toward the edge of the field compared to a comparably priced Plössl.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow will this 10mm eyepiece perform on the Orion Nebula (M42) in an 8\" f\/10 SCT?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eIn an 8\" f\/10 SCT, this 10mm eyepiece will provide 203x magnification. This is an excellent power for examining the core of the Orion Nebula (M42), easily resolving the four primary stars of the Trapezium cluster (Theta-1 Orionis) and revealing the intricate gas clouds and structures immediately surrounding them.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Explore Scientific 10mm 52° a good choice for globular clusters like M13 in a 6\" f\/8 Dobsonian?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, it's a great choice. In a 6\" f\/8 Dobsonian, a 10mm eyepiece yields 122x magnification. This is often the sweet spot for resolving the dense core of the Hercules Cluster (M13) into individual stars while keeping the cluster beautifully framed within the 52° field of view.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy is a 10mm eyepiece considered a 'workhorse' focal length?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eA 10mm eyepiece provides a significant step up in magnification from low-power \"finder\" eyepieces without being so powerful that the view is easily blurred by atmospheric turbulence. It's versatile enough for planetary viewing on steady nights, resolving details in galaxies, and studying planetary nebulae, making it one of the most frequently used eyepieces in a collection.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is 'averted vision' and why is this eyepiece good for it?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAverted vision is the technique of looking slightly to the side of a faint object to see it more clearly. This places the image on a part of your retina that is more sensitive to low light. The Explore Scientific 10mm 52° eyepiece is excellent for this because its \u003cstrong\u003ehigh-contrast optics\u003c\/strong\u003e make the faint glow of deep-sky objects stand out more distinctly from the black sky background, making the technique more effective.\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\u003e10mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eApparent Field of View\u003c\/td\u003e\n\u003ctd\u003e52°\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\u003eWaterproof\u003c\/td\u003e\n\u003ctd\u003eYes, Argon-Purged\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eGTIN\u003c\/td\u003e\n\u003ctd\u003e811803030039\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\"\u003eExplore Scientific 52° 10mm 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":44967200162077,"sku":"ES-EPWP5210-01","price":97.99,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Explore-Scientific-10mm-52-deg-Series-Waterproof-Eyepiece-EPWP5210-01-1__02175.1594240350.1280.1280.jpg?v=1684338755"},{"product_id":"explore-scientific-52-15mm-waterproof-eyepiece-1-25","title":"Explore Scientific 52° 15mm Waterproof Eyepiece - 1.25\"","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e15mm Focal Length\u003c\/li\u003e\n\u003cli\u003e52° Apparent Field of View\u003c\/li\u003e\n\u003cli\u003e1.25\" Barrel Diameter\u003c\/li\u003e\n\u003cli\u003eWaterproof, Argon-Purged Construction\u003c\/li\u003e\n\u003cli\u003eFlat-Field Multi-Element Optical Design\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\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 52° 15mm Waterproof Eyepiece - 1.25\"\u003c\/h2\u003e\n      \u003cp\u003eThe Explore Scientific 52° 15mm Waterproof Eyepiece delivers essential mid-range magnification in a rugged 1.25\" barrel design. Its multi-element, flat-field optical system provides a sharp 52° apparent field of view, offering a distinct upgrade in edge-to-edge clarity over comparably priced Plössl eyepieces.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n\n  \u003cdiv class=\"DAV-bg-light\"\u003e\n    \u003cdiv class=\"DAV-section\"\u003e\n      \u003ch3\u003e15mm Focal Length: The Deep-Sky Workhorse\u003c\/h3\u003e\n      \u003cp\u003ePositioned squarely in the mid-magnification range for most telescopes, the 15mm focal length is a true workhorse for deep-sky observation. It provides a significant increase in image scale over low-power eyepieces, darkening the sky background to enhance contrast. This makes the faint arms of galaxies and the delicate structures within nebulae like the Lagoon Nebula (M8) more apparent, especially from suburban locations.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n\n  \u003cdiv class=\"DAV-bg-light\"\u003e\n    \u003cdiv class=\"DAV-section\"\u003e\n      \u003ch3\u003eA 52° Flat-Field View vs. a Standard Plössl\u003c\/h3\u003e\n      \u003cp\u003eWhile the 52° apparent field is only slightly wider than a typical Plössl, the true advantage of the Explore Scientific 52° series lies in its flat-field optical design. This advanced, multi-element construction corrects for field curvature, ensuring stars remain sharp points across the entire field of view, not just in the center.\u003c\/p\u003e\n      \u003cul\u003e\n        \u003cli\u003e\n\u003cstrong\u003eEdge-to-Edge Sharpness:\u003c\/strong\u003e Where a standard Plössl may show stars becoming elongated near the field stop, this eyepiece maintains tight, point-like stars for a more pleasing and detailed view.\u003c\/li\u003e\n        \u003cli\u003e\n\u003cstrong\u003eEnhanced Contrast:\u003c\/strong\u003e Superior coatings and internal baffling produce high-contrast images that make it easier to employ techniques like averted vision to detect the faintest details in objects.\u003c\/li\u003e\n      \u003c\/ul\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n\n    \u003cdiv class=\"DAV-bg-light\"\u003e\n    \u003cdiv class=\"DAV-section\"\u003e\n      \u003ch3\u003eArgon-Purged and Waterproof for Field Reliability\u003c\/h3\u003e\n      \u003cp\u003eUnlike standard eyepieces, every Explore Scientific 52° eyepiece is built to withstand harsh observing conditions. The optical housing is sealed and purged with inert argon gas, making it fully waterproof. This design offers two critical benefits for real-world astronomy.\u003c\/p\u003e\n      \u003cul\u003e\n        \u003cli\u003e\n\u003cstrong\u003eNo Internal Fogging:\u003c\/strong\u003e The argon-purged barrel prevents moisture from getting inside the eyepiece on dewy nights, eliminating the possibility of internal fogging that can end an observing session.\u003c\/li\u003e\n        \u003cli\u003e\n\u003cstrong\u003eEasy Cleaning \u0026amp; Longevity:\u003c\/strong\u003e The sealed optics are protected from fungus, dust, and moisture, ensuring a long service life. If the outer lens gets dirty, you can safely rinse the eyepiece under running water without risk.\u003c\/li\u003e\n      \u003c\/ul\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n\n\u003c\/div\u003e\n\u003c\/li\u003e\n\n\u003cli\u003e\n  \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eHow will the Explore Scientific 15mm 52° eyepiece perform on the Orion Nebula (M42) in an 8-inch f\/6 Dobsonian?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eIn an 8-inch f\/6 Dobsonian (1200mm focal length), the 15mm eyepiece yields 80x magnification. This is an excellent power for M42, providing enough image scale to resolve the four main stars of the Trapezium (Theta Orionis) while keeping the entire nebula, including its faint outer wings, comfortably within the 52° field of view.\u003c\/p\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eIs the 15mm focal length a good choice for globular clusters like M13 in an f\/10 SCT?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eYes, it's a great starting point. On a typical 8\" f\/10 SCT (2032mm focal length), the 15mm provides 135x magnification. This is often enough to begin resolving the dense core of the Hercules Cluster (M13) into individual stars from a dark sky site, and the high-contrast optics will help the cluster stand out against the darkened sky background.\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 Explore Scientific 15mm 52° over a standard 15mm Plössl?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eThe primary advantages are its \u003cstrong\u003eflat-field optics\u003c\/strong\u003e and \u003cstrong\u003ewaterproof construction\u003c\/strong\u003e. The flat field provides noticeably sharper stars at the edge of the view compared to a Plössl. The argon-purged, sealed body prevents internal fogging and makes the eyepiece far more durable for use in damp conditions.\u003c\/p\u003e\n  \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does 'Argon-Purged Waterproof' mean for the Explore Scientific 15mm eyepiece?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eThis means the eyepiece barrel is sealed with O-rings and filled with an inert gas (argon) that contains no water vapor. This process makes the eyepiece completely waterproof, prevents internal lenses from fogging up during temperature changes, and protects the delicate optical coatings from moisture, dust, and fungus over the long term.\u003c\/p\u003e\n  \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eWhy is the Explore Scientific 15mm 52° eyepiece good for 'averted vision'?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eThe product description highlights this because of the eyepiece's excellent contrast. Averted vision—looking slightly to the side of a faint object—works by placing the image on a more light-sensitive part of your retina. A high-contrast eyepiece makes this technique more effective by presenting a cleaner, darker background, which helps your eye detect the subtle glow of faint fuzzies like distant galaxies.\u003c\/p\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eIs the eye relief on the Explore Scientific 15mm 52° eyepiece suitable for eyeglass wearers?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eThe manufacturer does not publish a specific eye relief value for this eyepiece. While many observers find 52° designs comfortable, those who require eyeglasses to correct for significant astigmatism may not be able to see the full field of view. Eyeglass wearers typically need eyepieces with at least 15-20mm of eye relief for comfortable viewing.\u003c\/p\u003e\n  \u003c\/div\u003e\n\u003c\/li\u003e\n\n\u003cli\u003e\n  \u003ctable class=\"DAV-specifications\"\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n\u003ctd\u003eFocal Length\u003c\/td\u003e\n\u003ctd\u003e15mm\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eApparent Field of View\u003c\/td\u003e\n\u003ctd\u003e52°\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\u003eConstruction\u003c\/td\u003e\n\u003ctd\u003eWaterproof, Argon-Purged\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003eFlat-Field Multi-Element\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eGTIN\u003c\/td\u003e\n\u003ctd\u003e811803030046\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/li\u003e\n\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\"\u003eExplore Scientific 52° 15mm 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\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\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":44967200227613,"sku":"ES-EPWP5215-01","price":97.99,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Explore-Scientific-52-deg-15mm-Waterproof-Eyepiece-EPWP5215-01-1__87791.1594240350.1280.1280.jpg?v=1684338760"},{"product_id":"explore-scientific-52-20mm-waterproof-eyepiece-1-25","title":"Explore Scientific 52° 20mm Waterproof Eyepiece - 1.25\"","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e20mm Focal Length\u003c\/li\u003e\n\u003cli\u003e52° Apparent Field of View\u003c\/li\u003e\n\u003cli\u003e1.25\" Barrel Diameter\u003c\/li\u003e\n\u003cli\u003eWaterproof \u0026amp; Argon-Purged Construction\u003c\/li\u003e\n\u003cli\u003eFlat-Field Multi-Element Optical Design\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\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 52° 20mm Waterproof Eyepiece - 1.25\"\u003c\/h2\u003e\n\u003cp\u003eThe Explore Scientific 52° 20mm Waterproof Eyepiece delivers a generous 52° apparent field of view in a standard 1.25\" barrel, providing a significant upgrade over basic kit eyepieces. Its 20mm focal length produces a versatile mid-range magnification ideal for locating and framing a wide range of celestial objects, from open star clusters to large nebulae.\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 20mm Focal Length: A 52° Flat-Field View\u003c\/h3\u003e\n\u003cp\u003eThe 20mm focal length is often considered a \"workhorse\" for many amateur telescopes, offering a balance between a wide true field for context and enough magnification to resolve detail. The 52° apparent field feels more immersive than a typical Plössl and the flat-field multi-element design ensures stars remain sharp across the view, not just in the center.\u003c\/p\u003e\n\u003cp\u003eThis optical combination is ideal for sweeping the star fields of the Milky Way or stepping through the targets of a Messier Marathon. For observers with binoviewers, the compact size and comfortable view make the 20mm 52° an excellent choice for creating a matched pair.\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\u003eArgon-Purged Construction: A 1.25\" Eyepiece Sealed for Life\u003c\/h3\u003e\n\u003cp\u003eUnlike standard eyepieces, this 1.25\" ocular is fully waterproof and sealed with an inert argon gas purge. This process prevents internal fogging during nights with heavy dew and permanently protects the internal lens surfaces from dust, moisture, and fungus. You get a clean, high-contrast view every time you observe, without worrying about internal contamination.\u003c\/p\u003e\n\u003cp\u003eThe trade-off for this level of protection is that the eyepiece is sealed at the factory and not intended to be disassembled by the user. However, this robust construction ensures a lifetime of reliable use under all observing conditions.\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 52° 20mm vs. a Standard Plössl\u003c\/h3\u003e\n\u003cp\u003eWhile a Plössl is a classic design, the Explore Scientific 52° Series offers distinct advantages for a comparable price. The advanced optical design provides superior contrast, which is critical for teasing out faint details in galaxies and nebulae. This enhanced contrast also makes it easier to use averted vision—looking slightly to the side of a target to place it on a more light-sensitive part of your retina.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSuperior Contrast:\u003c\/strong\u003e The multi-element design and modern coatings deliver darker sky backgrounds and make faint objects \"pop\" more than in simpler four-element eyepieces.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWider, Flatter Field:\u003c\/strong\u003e The 52° apparent field is not only wider than many Plössls but is also better corrected towards the edge, keeping stars sharp across a larger portion of the view.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSealed Construction:\u003c\/strong\u003e The waterproof, argon-purged body offers a level of durability and protection against the elements that unsealed eyepieces cannot match.\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 makes the Explore Scientific 52° 20mm eyepiece different from a standard 20mm Plössl?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Explore Scientific 52° 20mm offers three main advantages over a comparably priced Plössl. It has a wider \u003cstrong\u003e52° apparent field of view\u003c\/strong\u003e, a \u003cstrong\u003eflat-field design\u003c\/strong\u003e for better edge-of-field sharpness, and a fully \u003cstrong\u003ewaterproof, argon-purged construction\u003c\/strong\u003e that prevents internal fogging and contamination.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the waterproof design of the ES 52° 20mm eyepiece benefit my observing?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe waterproof and argon-purged design prevents moisture from getting inside the eyepiece on dewy nights, eliminating the possibility of internal fogging. It also creates a sealed environment that protects the internal optics from dust, pollen, and fungus, ensuring the eyepiece maintains its original contrast and clarity for years.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Explore Scientific 52° 20mm a good eyepiece for binoviewing?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. As noted by Explore Scientific, its relatively small physical size and versatile magnification make the 20mm 52° Series a good selection for use in binoviewers. You can create a well-matched pair without adding excessive weight or balance issues to your telescope.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat kinds of objects are best viewed with the Explore Scientific 52° 20mm eyepiece?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe 20mm focal length is excellent for medium-power views of a wide variety of objects. It's ideal for framing \u003cstrong\u003elarge open clusters\u003c\/strong\u003e like the Pleiades (M45) or Beehive Cluster (M44), observing \u003cstrong\u003eextended nebulae\u003c\/strong\u003e like the Lagoon Nebula (M8), and locating targets when sweeping rich star fields.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow will the Explore Scientific 52° 20mm eyepiece perform on the Orion Nebula (M42) in an 8\" f\/10 SCT?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eIn a typical 8\" f\/10 SCT with a 2032mm focal length, the 20mm eyepiece will provide about 102x magnification. This is an excellent power for framing the entire Orion Nebula (M42), from the bright core of the Trapezium cluster out to the fainter \"wings\" of nebulosity, all within a single, high-contrast field of view.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the 20mm focal length suitable for a Messier Marathon with a 6\" f\/8 Dobsonian?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAbsolutely. A 6\" f\/8 Dobsonian has a focal length of around 1200mm, where the 20mm eyepiece yields 60x magnification and a true field of view of approximately 0.87 degrees. This is a perfect \"finder\" magnification for a Messier Marathon, wide enough to easily locate objects but with enough power to identify them clearly.\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\u003e20mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eApparent Field of View\u003c\/td\u003e\n\u003ctd\u003e52°\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\u003eConstruction\u003c\/td\u003e\n\u003ctd\u003eWaterproof, Argon-Purged\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eGTIN\u003c\/td\u003e\n\u003ctd\u003e811803030053\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\"\u003eExplore Scientific 52° 20mm 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\"\u003eDust Caps\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 2\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\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":44967200293149,"sku":"ES-EPWP5220-01","price":97.99,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Explore-Scientific-20mm-52-deg-Series-Waterproof-Eyepiece-EPWP5220-01-1__67213.1594240351.1280.1280.jpg?v=1684338766"},{"product_id":"explore-scientific-52-25mm-waterproof-eyepiece-1-25","title":"Explore Scientific 52° 25mm Waterproof Eyepiece - 1.25\"","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e25mm Focal Length\u003c\/li\u003e\n\u003cli\u003e52° Apparent Field of View\u003c\/li\u003e\n\u003cli\u003e1.25\" Barrel Diameter\u003c\/li\u003e\n\u003cli\u003eWaterproof \u0026amp; Argon-Purged Construction\u003c\/li\u003e\n\u003cli\u003eWeighs 6.4 oz (181.4 g)\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 52° 25mm Waterproof Eyepiece - 1.25\"\u003c\/h2\u003e\n\u003cp\u003eThe Explore Scientific 52° 25mm Waterproof Eyepiece delivers a generous 52° apparent field of view in a standard 1.25\" barrel format. As a multi-element, flat-field ocular weighing just 6.4 oz, it serves as a significant optical upgrade over basic eyepieces, providing a comfortable, high-contrast view at the versatile 25mm focal length.\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 Flat-Field 52° View Beyond Standard Plössls\u003c\/h3\u003e\n\u003cp\u003eWith a 52° apparent field, this eyepiece offers an immersive window that feels wider and more comfortable than many traditional designs. Its flat-field optics correct for distortions at the edge of view, ensuring stars remain sharp across the entire field, not just in the center. This correction, combined with excellent contrast, makes it easier to detect faint details in galaxies and nebulae.\u003c\/p\u003e\n\u003cp\u003eThe high-contrast image is particularly effective for using averted vision—looking slightly to the side of a dim object. This technique places the image on a more light-sensitive part of your retina, and the clean, dark background of the 52° 25mm eyepiece makes those faint fuzzies pop into view more readily.\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 6.4 oz Argon-Purged Waterproof Optic\u003c\/h3\u003e\n\u003cp\u003eBuilt to withstand demanding field conditions, the eyepiece is fully waterproof and purged with inert argon gas. This process prevents internal fogging during nights with heavy dew and protects the internal lens coatings from moisture and fungus, ensuring a lifetime of use. The durable construction adds reliability without excessive mass.\u003c\/p\u003e\n\u003cp\u003eAt a lightweight 6.4 oz (181.4 g), the 52° 25mm is easy to handle and helps maintain your telescope's balance, especially when used in pairs for a binoviewer. Its low weight makes it an ideal workhorse eyepiece that you can switch in and out without needing to rebalance the optical tube.\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\"\u003eWhat makes the Explore Scientific 25mm 52° eyepiece better than a standard Plössl?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWhile sharing a similar apparent field, the Explore Scientific 52° 25mm uses a more advanced \u003cstrong\u003emulti-element, flat-field design\u003c\/strong\u003e. This results in sharper stars at the edge of the field and typically offers better contrast and eye comfort compared to a comparably priced, simpler Plössl eyepiece.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does 'Argon-Purged Waterproof' mean for the 25mm 52° eyepiece?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThis means the eyepiece barrel is sealed and filled with inert argon gas. This process achieves two key benefits:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eWaterproofing:\u003c\/strong\u003e It prevents moisture, dew, or rain from getting inside the eyepiece.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAnti-Fogging:\u003c\/strong\u003e It stops internal lenses from fogging up when moving from a warm house to a cold observing site, ensuring a clear view all night.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow will the Explore Scientific 25mm eyepiece perform for finding faint objects like the Andromeda Galaxy (M31) in a 10\" Dobsonian?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eIn a typical 10\" f\/5 Dobsonian (1250mm focal length), the 25mm eyepiece provides 50x magnification. This is an ideal low-power magnification for framing large objects like the Andromeda Galaxy (M31) or the North American Nebula (NGC 7000), making it an excellent \"finder\" eyepiece for locating and centering deep-sky targets before increasing magnification.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Explore Scientific 25mm 52° a good choice for a binoviewer?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, it's an excellent choice. Its light weight of only \u003cstrong\u003e6.4 oz\u003c\/strong\u003e means a pair of them won't put excessive strain on your focuser or require significant counterweights. The comfortable view also makes extended observing with two eyes much more enjoyable.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eI have an 8\" f\/10 SCT. What kind of views can I expect with the 25mm 52° eyepiece on the Orion Nebula (M42)?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eOn a typical 8\" SCT with a 2032mm focal length, the 25mm eyepiece yields 81x magnification. This is a perfect magnification for framing the entire Orion Nebula (M42), from the bright Trapezium stars at its core to the faint, sweeping outer loops of nebulosity, all within a single high-contrast field of view.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is averted vision, and why is this 25mm eyepiece good for it?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003e\u003cstrong\u003eAverted vision\u003c\/strong\u003e is the technique of looking slightly to the side of a faint object to see it more clearly. The Explore Scientific 52° 25mm eyepiece has excellent contrast and a dark background, which makes it easier for the faint light from objects like nebulae or galaxies to be detected by the more sensitive peripheral parts of your vision.\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\u003e25mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eApparent Field of View\u003c\/td\u003e\n\u003ctd\u003e52°\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\u003eWaterproof\u003c\/td\u003e\n\u003ctd\u003eYes, Argon-Purged\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e6.4 oz \/ 181.4 g\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eGTIN\u003c\/td\u003e\n\u003ctd\u003e811803030060\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\"\u003eExplore Scientific 52° 25mm 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":44967200325917,"sku":"ES-EPWP5225-01","price":111.99,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Explore-Scientific-25mm-52-deg-Series-Waterproof-Eyepiece-EPWP5225-01-1__63744.1594240352.1280.1280.jpg?v=1684338771"},{"product_id":"explore-scientific-52-30mm-waterproof-eyepiece-1-25","title":"Explore Scientific 52° 30mm Waterproof Eyepiece - 1.25\"","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e30mm Focal Length\u003c\/li\u003e\n\u003cli\u003e52° Apparent Field of View\u003c\/li\u003e\n\u003cli\u003e1.25\" Barrel Diameter\u003c\/li\u003e\n\u003cli\u003eWaterproof \u0026amp; Argon-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 52° 30mm Waterproof Eyepiece - 1.25\"\u003c\/h2\u003e\n\u003cp\u003eThe Explore Scientific 52° 30mm Waterproof Eyepiece yields an expansive true field of view from a standard 1.25\" barrel. Its 30mm focal length produces the low magnification needed for locating faint objects, and the 52° apparent field creates a comfortable, flat-field window on large nebulae and galaxies.\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 Focal Length Advantage: Wide Fields for Deep Sky\u003c\/h3\u003e\n\u003cp\u003eA 30mm eyepiece is a critical tool for any deep-sky observer. It produces a large exit pupil that floods your eye with light, revealing the faint, extended details in galaxies and nebulae. This low-power, wide-field view is essential for initially locating targets and is often the best choice for framing large objects like the Andromeda Galaxy (M31) or the North American Nebula (NGC 7000) in their entirety.\u003c\/p\u003e\n\u003cp\u003eWhen atmospheric seeing is poor, high magnification only amplifies the turbulence. The low power of the 30mm eyepiece maintains a stable, sharp image, allowing you to continue observing when other eyepieces would be unusable. It serves as the ideal starting point for any observing session, giving you the \"big picture\" view of the sky.\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\u003e52° Flat-Field Optics for High-Contrast Views\u003c\/h3\u003e\n\u003cp\u003eThe Explore Scientific 52° series uses a multi-element, flat-field optical design that pushes it beyond a simple Plössl. The 52° apparent field is comfortable and immersive, but its real strength is the exceptional contrast and edge-to-edge sharpness. This optical correction is vital for discerning subtle details in faint objects.\u003c\/p\u003e\n\u003cp\u003eThis high contrast makes the eyepiece particularly effective for using averted vision—the technique of looking slightly to the side of a faint object. By placing the image on a more light-sensitive part of your retina, you can perceive details that are otherwise invisible. The clean, dark background of this eyepiece makes that technique significantly more productive.\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\u003eArgon-Purged for a Lifetime of Waterproof Integrity\u003c\/h3\u003e\n\u003cp\u003eUnlike standard eyepieces, the Explore Scientific 52° 30mm is a fully sealed and waterproof unit. The optical housing is purged of air and filled with inert argon gas. This process makes it impossible for internal fogging to occur, even during nights with heavy dew, and permanently protects the internal lens surfaces from dust, fungus, and moisture.\u003c\/p\u003e\n\u003cp\u003eThis robust construction ensures that the eyepiece will maintain its out-of-the-box optical clarity for years without needing internal cleaning. The trade-off for this durability is that the sealed unit cannot be disassembled by the user, but the design ensures it will never need to be.\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\u003eES 52° 30mm vs. a Standard 1.25\" Plössl\u003c\/h3\u003e\n\u003cp\u003eWhile a 30mm or 32mm Plössl is a common low-power eyepiece, the Explore Scientific 52° 30mm represents a significant step up in optical design and user comfort. A direct comparison reveals several key advantages for the deep-sky observer.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eFlat Field:\u003c\/strong\u003e Standard Plössls often exhibit some field curvature, meaning stars near the edge of the view are not perfectly sharp. The multi-element design of the ES 52° eyepiece is corrected to produce a flatter field, keeping stars tight across the entire view.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEye Relief:\u003c\/strong\u003e This eyepiece is designed for superior viewing comfort compared to many Plössls, making it easier to hold your eye position for long, relaxed observing sessions.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eContrast:\u003c\/strong\u003e Enhanced baffling and modern multi-coatings contribute to a darker sky background, which is crucial for picking out the faintest details in galaxies and nebulae.\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\"\u003eWhy choose the Explore Scientific 52° 30mm eyepiece for finding objects?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe \u003cstrong\u003e30mm focal length\u003c\/strong\u003e produces a very wide true field of view, showing you a much larger patch of sky than a high-power eyepiece. This makes it significantly easier to star-hop and locate your target object before switching to higher magnifications.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the ES 52° 30mm eyepiece help in viewing large objects like the Andromeda Galaxy (M31) through a Schmidt-Cassegrain telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eSchmidt-Cassegrains (SCTs) have long focal lengths, which can make it difficult to fit large deep-sky objects into the field of view. The Explore Scientific 52° 30mm eyepiece provides the lowest practical magnification, ensuring that you can see the full extent of large targets like the Andromeda Galaxy (M31) or the Pleiades (M45) within a single, well-framed view.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does \"Argon-Purged Waterproof\" mean for the ES 52° 30mm eyepiece?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThis means the eyepiece is hermetically sealed to prevent moisture, dust, or fungus from ever entering the optical housing. The air inside has been replaced with \u003cstrong\u003einert argon gas\u003c\/strong\u003e, which stops internal lens surfaces from fogging up on cold, humid nights. It ensures the eyepiece remains internally pristine for its entire lifespan.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the ES 52° 30mm a good choice for a portable, short-focal-length refractor?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, it's an excellent match. On a short refractor, this eyepiece will function as a \"finder\" eyepiece, delivering an extremely wide true field of view for sweeping the Milky Way's star fields and observing large emission nebulae like the North American Nebula (NGC 7000).\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat are the main benefits of the Explore Scientific 52° 30mm over a similarly priced Plössl eyepiece?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eCompared to a standard Plössl, the Explore Scientific 52° 30mm offers a \u003cstrong\u003eflatter field of view\u003c\/strong\u003e (sharper stars at the edge), generally \u003cstrong\u003ebetter eye relief\u003c\/strong\u003e for more comfortable viewing, and a sealed, \u003cstrong\u003ewaterproof build\u003c\/strong\u003e for enhanced durability and longevity.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill I see the shadow of my secondary mirror with this 30mm eyepiece?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eIn very \"fast\" telescopes (f\/5 or lower), a 30mm eyepiece can produce an exit pupil so large that you may notice the dark silhouette of your telescope's secondary mirror. However, in most common telescopes like f\/8 refractors or f\/10 Schmidt-Cassegrains, the exit pupil is smaller and this is rarely an issue during nighttime observing.\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\u003e30mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eApparent Field of View\u003c\/td\u003e\n\u003ctd\u003e52°\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\u003eGTIN\u003c\/td\u003e\n\u003ctd\u003e811803030077\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\"\u003eExplore Scientific 52° 30mm 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\u003cp\u003eNo manual or software is available for this product.\u003c\/p\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 Policy\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Explore Scientific","offers":[{"title":"Default Title","offer_id":44967200358685,"sku":"ES-EPWP5230-01","price":139.99,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Explore-Scientific-30mm-52-deg-Series-Waterproof-Eyepiece-EPWP5230-01-1__12318.1594240352.1280.1280.jpg?v=1684338847"},{"product_id":"explore-scientific-52-40mm-waterproof-eyepiece-2","title":"Explore Scientific 52° 40mm Waterproof Eyepiece - 2\"","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e40mm Focal Length\u003c\/li\u003e\n\u003cli\u003e52° Apparent Field of View\u003c\/li\u003e\n\u003cli\u003e2\" Diameter Barrel\u003c\/li\u003e\n\u003cli\u003eWaterproof and Argon-Purged Construction\u003c\/li\u003e\n\u003cli\u003eFully Multi-Coated, Flat-Field Optics\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 52° 40mm Waterproof Eyepiece - 2\"\u003c\/h2\u003e\n\u003cp\u003eThe Explore Scientific 52° 40mm Waterproof Eyepiece delivers the widest possible true field of view for deep-sky observers using long focal length telescopes. Its 40mm focal length produces low magnification for scanning vast star fields, while the 52° apparent field offers a sharp, flat window that makes this the only 2-inch eyepiece in the 52° series.\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\u003eDeep-Sky Views: The 40mm Focal Length Advantage\u003c\/h3\u003e\n\u003cp\u003eWith a 40mm focal length, this eyepiece is engineered for observers hunting the faintest objects at the limit of their telescope's reach. The low magnification darkens the sky background and increases surface brightness, making it ideal for framing large targets like the Andromeda Galaxy (M31), the Rosette Nebula (NGC 2244), and sprawling open star clusters.\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 52° Flat-Field Window on the Sky\u003c\/h3\u003e\n\u003cp\u003eUnlike a standard Plössl, the Explore Scientific 52° 40mm uses a multi-element, flat-field optical design. This corrects for field curvature, keeping stars sharp across the entire 52° apparent field. The high-contrast optics make it easier to use averted vision—looking slightly to the side of a faint object—to detect subtle details in galactic structure or faint nebulosity that would otherwise be invisible.\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\u003eBuilt for the Field: Argon-Purged and Waterproof in a 2\" Barrel\u003c\/h3\u003e\n\u003cp\u003eDesigned for real-world observing conditions, this eyepiece is fully waterproof and purged with inert argon gas. This process prevents internal fogging during nights with heavy dew and stops contaminants like dust or fungus from ever entering the sealed optical path. As the only 2-inch model in the 52° lineup, it's built to provide a lifetime of reliable views.\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 40mm: 52° vs. 62° and 68° Series Eyepieces\u003c\/h3\u003e\n\u003cp\u003eExplore Scientific offers three distinct 40mm eyepieces, each serving a different purpose. The choice depends on your priority between an immersive field and maximum viewing comfort.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e52° Series (This Model):\u003c\/strong\u003e Offers the longest eye relief of the three. It's the top choice for observers who wear glasses or prefer the most comfortable, relaxed view without needing to press their eye close to the lens.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e62° and 68° Series:\u003c\/strong\u003e These eyepieces provide a significantly wider, more immersive apparent field of view. This \"spacewalk\" effect comes with shorter eye relief, making them better suited for observers who do not require eyeglasses.\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 52° 40mm eyepiece in an 8\" f\/10 SCT?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eIn a typical 8\" f\/10 SCT with a 2032mm focal length, the Explore Scientific 52° 40mm eyepiece yields 51x magnification and a wide true field of view. It's perfect for framing large deep-sky objects like the entire Andromeda Galaxy (M31), the North American Nebula (NGC 7000), the Veil Nebula complex in Cygnus, and large open clusters like the Pleiades (M45).\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does waterproofing help the Explore Scientific 52° 40mm eyepiece?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe \u003cstrong\u003ewaterproof and argon-purged\u003c\/strong\u003e construction prevents moisture from getting inside the eyepiece on dewy nights, which would cause internal fogging and ruin a view. It also creates a sealed environment that protects the internal multi-coatings from dust, pollen, and fungus for the life of the eyepiece.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy choose the Explore Scientific 52° 40mm over the 68° 40mm eyepiece?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe primary reason is \u003cstrong\u003eeye relief\u003c\/strong\u003e. The 52° 40mm model is designed for maximum viewing comfort, especially for observers who need to wear eyeglasses to correct for astigmatism. While the 68° version offers a wider, more immersive field, the 52° is the more practical choice if long eye relief is your priority.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Explore Scientific 52° 40mm eyepiece good for a fast f\/5 Dobsonian?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eIn an f\/5 telescope, this eyepiece produces a very large 8mm exit pupil (40mm \/ 5). Since most dark-adapted human pupils only open to 7mm, some of the light gathered by your telescope will be wasted. You may also see the shadow of your telescope's secondary mirror. It is generally better suited for telescopes with focal ratios of f\/6 or slower.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the benefit of a \"flat-field\" design in the Explore Scientific 52° 40mm eyepiece?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eA flat-field design corrects for optical aberrations that can make stars near the edge of the view appear blurry or stretched. With this eyepiece, stars remain sharp, point-like sources across the entire \u003cstrong\u003e52° apparent field of view\u003c\/strong\u003e, providing a more pleasing and accurate image, especially when scanning dense star fields in the Milky Way.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use 2\" filters with the Explore Scientific 52° 40mm eyepiece?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The 2-inch barrel of the Explore Scientific 52° 40mm eyepiece is threaded to accept standard 2-inch (M48x0.75) astronomy filters. This allows you to easily add nebula filters, light pollution filters, or polarizers to enhance your views.\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\u003eGTIN\u003c\/td\u003e\n\u003ctd\u003e811803030084\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\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":44967200424221,"sku":"ES-EPWP5240-01","price":209.99,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Explore-Scientific-40mm-52-deg-Series-Waterproof-Eyepiece-EPWP5240-01-1__01847.1594240353.1280.1280.jpg?v=1684338853"},{"product_id":"explore-scientific-52-4-5mm-waterproof-eyepiece-1-25","title":"Explore Scientific 52° 4.5mm Waterproof Eyepiece - 1.25\"","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eHigh-magnification focal length for detailed views\u003c\/li\u003e\n\u003cli\u003e52° apparent field of view\u003c\/li\u003e\n\u003cli\u003eStandard 1.25\" barrel format\u003c\/li\u003e\n\u003cli\u003eWaterproof and argon-purged for all-weather use\u003c\/li\u003e\n\u003cli\u003eFlat-field multi-element optical design\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 52° 4.5mm Waterproof Eyepiece - 1.25\"\u003c\/h2\u003e\n\u003cp\u003eThe Explore Scientific 52° 4.5mm Waterproof Eyepiece delivers high-magnification views ideal for planets, double stars, and compact deep-sky objects, weighing only 181.4 grams. With a 52° apparent field and a 1.25\" barrel, this ocular is built for any observing conditions thanks to its waterproof, argon-purged housing. The flat-field, multi-element design darkens the sky background, enhancing contrast for detailed observation.\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\u003eHigh-Power Planetary and Compact DSO Views\u003c\/h3\u003e\n\u003cp\u003eThis 4.5mm eyepiece is engineered for high magnification, bringing out fine details in planets and splitting tight double stars. It also excels on bright, compact deep-sky objects; the increased image scale makes planetary nebulae and globular clusters impressive as they fill the field of view. By concentrating light from the object and darkening the surrounding sky, this eyepiece significantly boosts contrast.\u003c\/p\u003e\n\u003cp\u003eAchieving these detailed views is highly dependent on atmospheric stability. The benefits of high power are only realized when seeing conditions are favorable enough to support a sharp, steady image.\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\u003eFlat-Field Optics for Enhanced Contrast\u003c\/h3\u003e\n\u003cp\u003eThe Explore Scientific 52° Series features a flat-field, multi-element optical system that provides sharp images across the entire field. This design delivers exceptional contrast, which is critical for teasing out faint details. It makes the skill of using averted vision more effective, allowing you to place a dim object slightly off-center in the field.\u003c\/p\u003e\n\u003cp\u003eBy doing so, the image falls on a part of your eye that is more sensitive to low light. This technique, aided by the eyepiece's clean optical presentation, can be the difference between detecting a faint galaxy's outer arm or missing it entirely.\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\u003eArgon-Purged All-Weather Construction\u003c\/h3\u003e\n\u003cp\u003eDesigned for reliability, the eyepiece is fully waterproof and purged with inert argon gas. This process prevents internal fogging, which can occur when moving from a warm house to a cold night, and protects the internal lens coatings from moisture-induced degradation over the long term. This robust construction ensures your eyepiece is ready to perform regardless of dew or humidity.\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\u003eAdvanced Multi-Element Design vs. Standard Plössls\u003c\/h3\u003e\n\u003cp\u003eWhile a Plössl is a classic design, the Explore Scientific 52° 4.5mm eyepiece offers a significant step up in optical sophistication for a comparable investment. Its multi-element, flat-field design provides better edge-of-field correction and contrast than what is typically found in a standard four-element Plössl. This results in a more immersive and comfortable viewing experience, especially during long planetary sessions where you are studying subtle features at high power.\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\"\u003eWhat objects are best observed with the Explore Scientific 4.5mm eyepiece?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Explore Scientific 4.5mm eyepiece is a high-power ocular, making it ideal for observing objects that benefit from high magnification. This includes resolving details on \u003cstrong\u003eplanets\u003c\/strong\u003e like Jupiter's cloud bands and Saturn's rings, splitting \u003cstrong\u003eclose double stars\u003c\/strong\u003e, and examining bright, compact \u003cstrong\u003edeep-sky objects\u003c\/strong\u003e like planetary nebulae (e.g., the Ring Nebula, M57) and the cores of globular clusters (e.g., 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 high magnification of the 4.5mm eyepiece help with faint objects?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eHigh magnification darkens the sky background. This increases the \u003cstrong\u003econtrast\u003c\/strong\u003e between a faint object and the surrounding sky, often making the object easier to see. While it doesn't make the object intrinsically brighter, the improved contrast can reveal subtle details that would be lost at lower powers. This is especially effective for small planetary nebulae and galaxies.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy is an argon-purged eyepiece like the Explore Scientific 4.5mm better than a standard one?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAn argon-purged eyepiece is sealed and filled with an inert gas, making it \u003cstrong\u003efully waterproof\u003c\/strong\u003e. This has two main benefits: it prevents internal lens surfaces from fogging up in humid conditions or with rapid temperature changes, and it protects the delicate optical coatings from long-term moisture damage and fungus growth, ensuring a longer lifespan.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the Explore Scientific 4.5mm eyepiece work well for viewing Mars in my 6\" f\/8 Dobsonian?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, this is an excellent scenario. In a 6\" f\/8 Dobsonian (which has a 1200mm focal length), the 4.5mm eyepiece would yield approximately 267x magnification. This is a powerful combination for observing Martian surface features like the polar ice caps and darker albedo regions, provided the atmospheric seeing is stable.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the advantage of the Explore Scientific 52° eyepiece over a basic Plössl eyepiece?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Explore Scientific 52° eyepiece uses a more advanced \u003cstrong\u003emulti-element, flat-field design\u003c\/strong\u003e. Compared to a comparably priced Plössl, this typically provides better sharpness at the edge of the field of view and superior contrast. This results in a more comfortable and detailed image, especially for observers who spend a lot of time studying targets at high power.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the 4.5mm focal length too much power for my telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe maximum useful magnification is typically about 50x to 60x per inch of aperture under excellent seeing conditions. For a 4-inch telescope, this is around 200x-240x. The 4.5mm eyepiece will exceed this on many telescopes, making it very sensitive to atmospheric turbulence. It will perform best in telescopes with shorter focal lengths or on nights of exceptionally steady air.\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\u003e4.5mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eApparent Field of View\u003c\/td\u003e\n\u003ctd\u003e52°\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\u003eEye Relief\u003c\/td\u003e\n\u003ctd\u003eData not available\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLens Elements\u003c\/td\u003e\n\u003ctd\u003eData not available\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCoatings\u003c\/td\u003e\n\u003ctd\u003eMulti-coated\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWaterproof\u003c\/td\u003e\n\u003ctd\u003eYes, Argon-Purged\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e6.4 oz (181.4 g)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eGTIN\u003c\/td\u003e\n\u003ctd\u003e811803030015\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\"\u003eExplore Scientific 52° 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\"\u003eDust Caps\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 2\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":44967200456989,"sku":"ES-EPWP5245-01","price":97.99,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Explore-Scientific-4-5mm-52-deg-Series-Waterproof-Eyepiece-EPWP5245-01-1__17085.1594240354.1280.1280.jpg?v=1684338858"},{"product_id":"explore-scientific-52-6-5mm-waterproof-eyepiece-1-25","title":"Explore Scientific 52° 6.5mm Waterproof Eyepiece - 1.25\"","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e6.5mm Focal Length\u003c\/li\u003e\n\u003cli\u003e52° Apparent Field of View\u003c\/li\u003e\n\u003cli\u003e1.25\" Barrel Diameter\u003c\/li\u003e\n\u003cli\u003eWaterproof and Argon-Purged Construction\u003c\/li\u003e\n\u003cli\u003eMulti-Coated, Flat-Field Optics\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 52° 6.5mm Waterproof Eyepiece - 1.25\"\u003c\/h2\u003e\n\u003cp\u003eThe Explore Scientific 52° 6.5mm Waterproof Eyepiece delivers high-magnification views in a standard 1.25\" barrel format. Its multi-element optical design produces a 52° apparent field of view, offering a noticeable upgrade in sharpness and contrast over a standard Plössl at the same 6.5mm focal length.\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 52° Flat-Field View Beyond Standard Plössls\u003c\/h3\u003e\n\u003cp\u003eThis eyepiece's multi-element, flat-field design pushes it beyond the performance of a typical Plössl. The 52° apparent field feels more immersive and makes it easier to track objects as they drift, especially on non-driven mounts. Stars remain sharp across the field, a critical factor when examining tight double stars or the cores of globular clusters.\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 6.5mm Focal Length: High Power for Ideal Seeing\u003c\/h3\u003e\n\u003cp\u003eA 6.5mm focal length provides high magnification, ideal for resolving fine detail on planetary surfaces, splitting close double stars, and examining planetary nebulae. Achieving sharp views at this power is challenging and depends on steady atmospheric seeing, precise telescope collimation, and thermal equilibrium. When conditions are right, the views delivered by the 6.5mm eyepiece are unforgettable.\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\u003eArgon-Purged Waterproofing: Dew-Proof and Dust-Proof Optics\u003c\/h3\u003e\n\u003cp\u003eUnlike standard eyepieces, the Explore Scientific 52° series is fully sealed and purged with inert argon gas. This process prevents internal fogging during nights with heavy dew and stops dust, fungus, or moisture from ever contaminating the internal lens surfaces. The result is an eyepiece that is easier to clean, more durable, and maintains its optical contrast for years of use in any climate.\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 52° vs. Plössl: A Step-Up in Contrast and Comfort\u003c\/h3\u003e\n\u003cp\u003eWhile a Plössl is a classic design, the Explore Scientific 52° 6.5mm offers tangible advantages. The primary benefit is improved contrast, which makes it easier to use averted vision to detect faint details or nebulae. This skill, which involves looking slightly to the side of an object, places the image on a more light-sensitive part of your retina, and the high-contrast background of this eyepiece makes that technique more effective.\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\"\u003eWhat objects are best suited for the Explore Scientific 52° 6.5mm eyepiece?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe 6.5mm focal length provides high power, making it ideal for small, bright objects. It excels at revealing detail on \u003cstrong\u003eplanets like Jupiter and Saturn\u003c\/strong\u003e, splitting \u003cstrong\u003eclose double stars\u003c\/strong\u003e, and resolving the cores of \u003cstrong\u003ebright globular clusters like M13\u003c\/strong\u003e. It is also excellent for viewing small \u003cstrong\u003eplanetary nebulae such as the Ring Nebula (M57)\u003c\/strong\u003e.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow will the Explore Scientific 6.5mm eyepiece perform on Jupiter with an 8\" f\/10 SCT?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eIn an 8\" f\/10 Schmidt-Cassegrain Telescope (2032mm focal length), the 6.5mm eyepiece will yield a magnification of 312x. This is an excellent power for observing Jupiter's cloud bands, the Great Red Spot, and shadow transits of its moons, provided you have good atmospheric seeing. The eyepiece's high contrast will help make these features stand out.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy is a waterproof, argon-purged eyepiece like the Explore Scientific 6.5mm useful?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe argon-purged, waterproof design provides two key benefits:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eDew Prevention:\u003c\/strong\u003e It prevents internal lens surfaces from fogging up in damp conditions, which is a common problem during long observing sessions.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLongevity:\u003c\/strong\u003e The sealed barrel protects the internal coatings from moisture, fungus, and dust, ensuring the eyepiece maintains its optical clarity and contrast for many years.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Explore Scientific 52° 6.5mm a significant upgrade over a standard 6mm Plössl?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, for several reasons. The Explore Scientific 52° eyepiece offers a \u003cstrong\u003eflatter field of view\u003c\/strong\u003e, meaning stars stay sharp closer to the edge. It also provides \u003cstrong\u003ebetter contrast\u003c\/strong\u003e, which is crucial for seeing faint details on planets or teasing out dim stars. Finally, its \u003cstrong\u003ewaterproof construction\u003c\/strong\u003e makes it far more durable and reliable in variable weather conditions.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the Explore Scientific 6.5mm eyepiece to split the Double-Double (Epsilon Lyrae) in my 4\" refractor?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAbsolutely. A 4-inch (102mm) refractor has the resolving power to split the components of Epsilon Lyrae, which are separated by about 2.5 arc-seconds. The high magnification provided by the 6.5mm eyepiece will be essential for cleanly separating the two pairs, making this a perfect combination for that classic observing challenge on a night of steady seeing.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eThe description mentions averted vision. How does the Explore Scientific 52° 6.5mm eyepiece help with this technique?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAverted vision works best when the object you're trying to see is set against a dark, high-contrast background. The Explore Scientific 52° eyepiece's advanced multi-coatings and optical design produce a very dark sky background with minimal scattered light. This boosts contrast, making it easier for the more sensitive parts of your peripheral vision to detect faint objects like the central star in the Ring Nebula (M57) or faint extensions of galaxies.\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\u003eGTIN\u003c\/td\u003e\n\u003ctd\u003e811803030022\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\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":44967200489757,"sku":"ES-EPWP5265-01","price":97.99,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Explore-Scientific-52-deg-6-5mm-Waterproof-Eyepiece-EPWP5265-01-1__17455.1594240354.1280.1280.jpg?v=1684338863"}],"url":"https:\/\/davidastro.com\/collections\/explore-scientific-52-series-eyepieces.oembed","provider":"David Astro","version":"1.0","type":"link"}