{"product_id":"orion-optics-uk-secondary-dew-heater-odk18tr-carbon-fibre","title":"Orion Optics UK Dew Heater for 18\" Secondary (ODK18Tr)","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eCustom-designed for the Orion Optics UK 18\" ODK secondary mirror\u003c\/li\u003e\n\u003cli\u003eProvides active heating to prevent dew formation\u003c\/li\u003e\n\u003cli\u003eLightweight carbon fibre construction\u003c\/li\u003e\n\u003cli\u003eEnsures maximum light transmission on humid nights\u003c\/li\u003e\n\u003cli\u003eSeamless integration with the ODK18Tr secondary assembly\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\u003eOrion Optics UK Dew Heater for 18\" Secondary (ODK18Tr)\u003c\/h2\u003e\n\u003cp\u003eThis Orion Optics UK Dew Heater is engineered specifically for the secondary mirror of the 18\" ODK telescope, providing an essential defence against dew. Built from lightweight carbon fibre, this heater ensures your ODK18Tr maintains pristine, high-contrast views throughout the longest imaging sessions, even as temperatures drop and humidity rises. It is the definitive solution for preventing the subtle, image-degrading effects of condensation on your secondary mirror.\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\u003eProtecting the ODK18 Secondary: Active Dew Prevention\u003c\/h3\u003e\n\u003cp\u003eAn open-tube design like the Orion Optics ODK18 is highly susceptible to dew, especially on the exposed secondary mirror which cools rapidly to the ambient temperature. This heater gently applies a small, consistent amount of heat directly to the secondary mirror assembly, keeping its surface just above the dew point without introducing tube currents or optical distortions. This active prevention is critical for long-exposure astrophotography, where even a thin film of dew can scatter light, reduce contrast, and ruin hours of data.\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\u003eODK18Tr Integration: Custom-Fit Carbon Fibre Construction\u003c\/h3\u003e\n\u003cp\u003eDesigned as the ODK18Tr secondary dew heater, this component integrates perfectly with the telescope's existing hardware. The use of carbon fibre ensures the unit adds minimal weight to the secondary assembly, preserving the telescope's precise collimation and balance. This custom fit guarantees an unobtrusive installation that does not interfere with the light path, maintaining the ODK's exceptional optical throughput while providing total protection from dew.\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\"\u003eWhy is a dedicated dew heater needed for the ODK18 secondary mirror?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe \u003cstrong\u003eOrion Optics UK 18\" ODK\u003c\/strong\u003e is a large, open-truss instrument, making its secondary mirror highly exposed to the night sky. This exposure causes it to cool quickly, often below the dew point, leading to condensation that degrades image quality. A dedicated heater is the only reliable way to keep the mirror surface clear all night.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the ODK18Tr Dew Heater introduce heat plumes or turbulence?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo. The heater is designed to apply very low, gentle warmth, typically raising the mirror temperature only a few degrees above ambient. When used with a proper dew controller that regulates power, it prevents dew formation without creating the kind of thermal gradients that cause visible tube currents or image distortion.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDo I need a separate dew controller for the ODK18Tr Heater?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. This is a heating element and requires an external dew controller to manage the power output. Using a controller is highly recommended as it allows you to apply only the necessary amount of heat, saving battery power and ensuring thermal stability.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-Q\"\u003eHow does the carbon fibre construction of the ODK18Tr heater benefit the telescope?\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003e\u003cstrong\u003eCarbon fibre\u003c\/strong\u003e is extremely strong and lightweight. By using this material, the heater adds negligible mass to the secondary mirror assembly, which is critical for maintaining the telescope's mechanical balance and holding collimation accurately throughout an imaging session.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs this dew heater compatible with other 18\" telescopes?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThis heater is specifically designed for the secondary mirror assembly of the \u003cstrong\u003eOrion Optics UK ODK18Tr\u003c\/strong\u003e. It is not a universal-fit heater and is unlikely to be compatible with secondary holders from other manufacturers, even on telescopes of a similar aperture.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does this heater improve imaging of faint targets like the Veil Nebula (NGC 6960)?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWhen imaging faint, low-contrast targets like the Veil Nebula, maintaining every bit of light transmission and contrast is essential. Dew on the secondary scatters faint light and reduces overall image brightness. The \u003cstrong\u003eODK18Tr Dew Heater\u003c\/strong\u003e ensures the optical surface remains perfectly clear, preserving the subtle details and faint wisps of nebulosity during the multi-hour exposures required for such objects.\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\u003eCompatibility\u003c\/td\u003e\n\u003ctd\u003eOrion Optics UK 18\" ODK Secondary Mirror (ODK18Tr)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMaterial\u003c\/td\u003e\n\u003ctd\u003eCarbon Fibre\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFunction\u003c\/td\u003e\n\u003ctd\u003eActive Dew Prevention Heater\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\/orion-optics-uk-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eOrion Optics UK 1-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Orion Optics UK","offers":[{"title":"Default Title","offer_id":52942374797597,"sku":"OOUK-SECONDARY-DEW-HEATER-ODK18TR-CARBON","price":1960.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Orion-Optics-UK-Logo_fd099893-d467-4593-a893-3a6b275ada1f.jpg?v=1789607114","url":"https:\/\/davidastro.com\/products\/orion-optics-uk-secondary-dew-heater-odk18tr-carbon-fibre","provider":"David Astro","version":"1.0","type":"link"}