{"title":"AG Optical Systems","description":"\u003cdiv\u003e\n  \u003cp\u003e\n    AG Optical Systems builds astrographs for people whose limiting factor is no longer the telescope. Carbon fibre truss structures that hold collimation through temperature swings, corrected Dall-Kirkham and Harmer-Wynne designs that deliver flat, coma-free fields across large sensors, and mechanical quality intended for permanent observatory installation. David Astro carries AG Optical Systems products in Canada, in stock, with fast shipping across Canada and worldwide.\n  \u003c\/p\u003e\n  \u003cp\u003e\n    These are serious instruments and a serious specification exercise, involving mount, sensor size, focuser and site. We are happy to work through it with you before anything is ordered.\n  \u003c\/p\u003e\n\u003c\/div\u003e\n\u003c!-- more --\u003e\n\u003cdiv\u003e\n  \u003ch2\u003eAstrograph Designs for Large Sensors\u003c\/h2\u003e\n  \u003cp\u003e\n    Every design here exists to produce a flat, well-corrected field at a long focal length, which is where most conventional telescopes fall short with a big chip.\n  \u003c\/p\u003e\n  \u003cul\u003e\n    \u003cli\u003e\n\u003cstrong\u003eCorrected Dall-Kirkham designs:\u003c\/strong\u003e An ellipsoidal primary with a spherical secondary plus a corrector group, giving a flat field and easier collimation than a classical Ritchey-Chretien.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eHarmer-Wynne designs:\u003c\/strong\u003e A corrector arrangement producing an exceptionally flat, well-corrected field across very large sensor formats.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eCarbon fibre truss structures:\u003c\/strong\u003e Very low thermal expansion, so focus and collimation hold as the temperature drops through a Canadian night.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eFully illuminated field size:\u003c\/strong\u003e The specification that matters most with a large sensor, and one that varies considerably between designs at the same aperture.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eFocuser and rotator provision:\u003c\/strong\u003e Designed to carry heavy instrument packages squarely, which is not a given on telescopes of this focal length.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eMount requirements:\u003c\/strong\u003e Long focal length demands a mount with guiding accuracy well beyond what a portable setup provides.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/div\u003e\n\u003cdiv\u003e\n  \u003ch2\u003eWhy Choose David Astro for AG Optical Systems\u003c\/h2\u003e\n  \u003cp\u003e\n    At this level, the telescope is rarely the thing that limits the result. The mount, the site and the guiding usually are.\n  \u003c\/p\u003e\n  \u003cul\u003e\n    \u003cli\u003e\n\u003cstrong\u003eWhole-system honesty:\u003c\/strong\u003e We will tell you if your mount or your typical seeing will not let a given aperture and focal length perform, before you buy the telescope.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eIlluminated field matched to sensor:\u003c\/strong\u003e We check the design's fully corrected field against your intended sensor, since that determines the real usable image.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eInstallation planning:\u003c\/strong\u003e Pier, clearance and cabling planned alongside the optic, because these are difficult to change once installed.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eAuthorized dealer:\u003c\/strong\u003e Full manufacturer warranty with support handled domestically in Canada.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eShips from Canada:\u003c\/strong\u003e No duties or brokerage fees for Canadian buyers on high-value optics.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/div\u003e\n\u003cdiv\u003e\n  \u003ch2\u003eAG Optical Systems in Canada — Frequently Asked Questions\u003c\/h2\u003e\n  \u003cdl\u003e\n    \u003cdt\u003e\u003cstrong\u003eWhat is a corrected Dall-Kirkham?\u003c\/strong\u003e\u003c\/dt\u003e\n    \u003cdd\u003eA Cassegrain variant using an ellipsoidal primary and spherical secondary with a corrector group. It is considerably easier to collimate than a Ritchey-Chretien and delivers a flat field across large sensors.\u003c\/dd\u003e\n    \u003cdt\u003e\u003cstrong\u003eWhy carbon fibre?\u003c\/strong\u003e\u003c\/dt\u003e\n    \u003cdd\u003eVery low thermal expansion. A metal truss changes length measurably as temperature drops, shifting focus through the night. Carbon holds focus and collimation far better across a Canadian temperature swing.\u003c\/dd\u003e\n    \u003cdt\u003e\u003cstrong\u003eWhat mount do I need?\u003c\/strong\u003e\u003c\/dt\u003e\n    \u003cdd\u003eOne with guiding accuracy suited to the focal length, which generally means an observatory-class equatorial with encoders or excellent periodic error. The mount is usually the constraint, not the optic.\u003c\/dd\u003e\n    \u003cdt\u003e\u003cstrong\u003eIs my seeing good enough?\u003c\/strong\u003e\u003c\/dt\u003e\n    \u003cdd\u003eAt long focal length, seeing frequently limits resolution below what the optics deliver. We will discuss realistic expectations for your site before recommending an aperture and focal length.\u003c\/dd\u003e\n  \u003c\/dl\u003e\n\u003c\/div\u003e\n\u003cdiv\u003e\n  \u003ch2\u003eSpecifying an astrograph?\u003c\/h2\u003e\n  \u003cp\u003eTell us your mount, sensor and site and we will work through the whole system. Canadian stock and support.\u003c\/p\u003e\n\u003c\/div\u003e","products":[],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/collections\/AG-Optical-Logo.jpg?v=1683749524","url":"https:\/\/davidastro.com\/fr-us\/collections\/ag-optical-systems.oembed","provider":"David Astro","version":"1.0","type":"link"}