{"product_id":"televue-oculare-nagler-31mm-type-5-2-grandangolare","title":"TeleVue Nagler 31mm Type 5 Eyepiece 2“ — 82° AFOV","description":"\u003cp\u003eThe \u003cstrong\u003eTeleVue Nagler 31mm Type 5\u003c\/strong\u003e is the legendary \"king of the field\": affectionately nicknamed \"Uncle Al's hand grenade\" by observers for its stocky shape, it offers the widest true field achievable in a 2\" barrel with an \u003cstrong\u003e82°\u003c\/strong\u003e apparent field of view, without giving up the razor-sharp performance that defines the Nagler series.\u003c\/p\u003e\n\n\u003ch3\u003eThe widest true field ever achieved in a 2\" barrel\u003c\/h3\u003e\n\u003cp\u003eBuilding a 31mm Nagler by simply scaling up the classic formula would have produced an enormous, extremely heavy eyepiece. TeleVue solved the problem with an \u003cstrong\u003einnovative 6-element design\u003c\/strong\u003e, some elements over 70mm in diameter, using four types of special glass. The result is a \u003cstrong\u003e42mm field stop\u003c\/strong\u003e, the widest possible in a 2\" barrel without resorting to a 3\" focuser, with a true field area 82% larger than the 22mm Nagler Type 4.\u003c\/p\u003e\n\n\u003ch3\u003eIdeal for Dobsonians and fast Newtonians\u003c\/h3\u003e\n\u003cp\u003eThanks to its wide field, owners of Dobsonians or fast Newtonians can observe without the secondary-mirror shadowing that affects other wide-field eyepieces at this focal length, and with longer intervals between manual nudges. The \u003cstrong\u003e19mm eye relief\u003c\/strong\u003e ensures comfortable viewing even with glasses. Note the significant weight (nearly 1kg): on large Dobsonians, switching from a lighter eyepiece to this one may require rebalancing.\u003c\/p\u003e\n\n\u003ch3\u003eConstruction and compatibility\u003c\/h3\u003e\n\u003cp\u003eThe \u003cstrong\u003e2\" (50.8mm) barrel\u003c\/strong\u003e features filter threads for standard astronomy filters, a rubber grip and a safety undercut groove. Lens edges are blackened for maximum contrast. Like every TeleVue eyepiece, it undergoes a 100% full-field visual inspection before shipping.\u003c\/p\u003e\n\n\u003ch3\u003eTechnical specifications\u003c\/h3\u003e\n\u003ctable\u003e\u003ctbody\u003e\n\u003ctr\u003e\u003cth\u003eProduct code\u003c\/th\u003e\u003ctd\u003eEN5-31.0\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003cth\u003eSeries\u003c\/th\u003e\u003ctd\u003eNagler Type 5\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003cth\u003eFocal length\u003c\/th\u003e\u003ctd\u003e31 mm\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003cth\u003eApparent field of view (AFOV)\u003c\/th\u003e\u003ctd\u003e82°\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003cth\u003eEye relief\u003c\/th\u003e\u003ctd\u003e19 mm\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003cth\u003eOptical elements\u003c\/th\u003e\u003ctd\u003e6\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003cth\u003eField stop\u003c\/th\u003e\u003ctd\u003e42 mm\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003cth\u003eOptical coating\u003c\/th\u003e\u003ctd\u003eProprietary TeleVue multi-layer, blackened lens edges\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003cth\u003eBarrel\u003c\/th\u003e\u003ctd\u003e2\" (50.8mm) with filter threads\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003cth\u003eEyecup\u003c\/th\u003e\u003ctd\u003eRubber, fold-down\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003cth\u003eWeight\u003c\/th\u003e\u003ctd\u003e998 g\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003cth\u003eLength\u003c\/th\u003e\u003ctd\u003e133 mm\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003cth\u003eMade in\u003c\/th\u003e\u003ctd\u003eUSA — TeleVue Optics\u003c\/td\u003e\u003c\/tr\u003e\n\u003c\/tbody\u003e\u003c\/table\u003e","brand":"TeleVue","offers":[{"title":"Default Title","offer_id":58612523598155,"sku":"TV14211","price":999.0,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0886\/1981\/1147\/files\/televue-nagler-31mm-type-5-oculare-82-gradi-afov-1.jpg?v=1790500510","url":"https:\/\/adriasky.it\/en\/products\/televue-nagler-31mm-type-5-eyepiece-wide-angle","provider":"Adriasky","version":"1.0","type":"link"}