{"product_id":"n-a-114mm-d114-f900mm-newtonian-primary-25mm-secondary","title":"N \/A 114mm D114 F900mm Newtonian Primary \u0026 25mm Secondary","description":"\u003cp\u003e\u003cstrong\u003eThis D114F900mm replacement main mirror with a 25mm short-axis secondary mirror is a K9-glass optical component set designed to restore or upgrade small Newtonian telescopes for clearer planetary and deep-sky viewing.\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cp\u003eIf you need a direct-replacement or spare optical train for a beginner Newtonian or travel scope, this pair gives you a 114mm diameter primary mirror with a 900mm focal length plus a 25mm short-side secondary mirror. Both optics are made from K9 glass and receive an aluminum reflective coating with an aluminum-oxide protective layer. The components ship in separate packaging so they arrive protected and ready to install in compatible focuser and secondary holder assemblies.\u003c\/p\u003e\n\n\u003ch3\u003eWhat performance can I expect from a 114mm K9 primary with a 900mm focal length?\u003c\/h3\u003e\n\u003cp\u003eThis mirror delivers a mid-aperture light-gathering area suitable for bright planets, the Moon, and many brighter deep-sky targets. The f\/7.9 focal ratio balances magnification potential and eyepiece compatibility for general observing and simple astrophotography.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003e114 mm aperture gives improved resolution versus small toy scopes\u003c\/li\u003e\n  \u003cli\u003e900 mm focal length (f\/7.9) supports medium to high eyepiece magnifications\u003c\/li\u003e\n  \u003cli\u003eK9 glass substrate provides stable figure for visual use\u003c\/li\u003e\n  \u003cli\u003eAluminum + protective oxide coating enhances reflectivity and durability\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eHow does the 25mm short-axis secondary mirror affect views and setup?\u003c\/h3\u003e\n\u003cp\u003eThe short-axis 25mm secondary presents a compact obstruction that keeps the light path efficient for small Newtonians and reduces weight in travel setups. It’s sized to match small-diameter primary mirrors and is suitable for adult or children’s beginner telescopes that use a similar secondary holder geometry.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003e25 mm short-axis minimizes central obstruction while fully illuminating common eyepieces\u003c\/li\u003e\n  \u003cli\u003eSpherical secondary is simple to align in collimation procedures\u003c\/li\u003e\n  \u003cli\u003eAluminized with protective film for handling and installation safety\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eHow easy is installation and what accessories do I need?\u003c\/h3\u003e\n\u003cp\u003eThese optics are replacement components intended for users familiar with collimation and basic mechanical installation in Newtonian tube assemblies. Installation requires a compatible secondary holder, focuser, and basic collimation tools; no specialized adhesives are necessary if the scope already has standard fittings.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eFits telescopes designed for a 114mm primary with a 25mm-compatible secondary\u003c\/li\u003e\n  \u003cli\u003eRequires a collimation cap or laser and a screwdriver for mounting adjustments\u003c\/li\u003e\n  \u003cli\u003ePackaged separately to reduce dust and handling damage during shipping\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eWho is this for: This mirror pair is intended for amateur astronomers replacing or upgrading optics on entry-level Newtonian reflector telescopes, travel scopes, and educational telescopes. It’s a practical choice for hobbyists wanting a robust K9 glass primary with a compact secondary for planetary observation and casual astrophotography experiments, as well as for telescope builders needing standardized mirror sizes for custom tubes.\u003c\/p\u003e\n\u003csection class=\"product-faq-snippet\"\u003e\u003ch3\u003eFAQ\u003c\/h3\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Will this mirror set fit my existing beginner Newtonian telescope?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: If your telescope accepts a 114mm primary and a ~25mm secondary, it should fit; check tube cell and secondary holder dimensions first.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Can I use this mirror for simple planetary photography?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: Yes—many users report usable planetary images; combine with a suitable eyepiece camera, short exposures, and accurate tracking.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/section\u003e","brand":"N \/A","offers":[{"title":"Default Title","offer_id":48412970287261,"sku":"B08C2XPD27","price":42.72,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0766\/9596\/1757\/files\/astronomical-telescope-main-mirror-front-view.jpg?v=1781254461","url":"https:\/\/nexoltic.com\/products\/n-a-114mm-d114-f900mm-newtonian-primary-25mm-secondary","provider":"Nexoltic","version":"1.0","type":"link"}