{"product_id":"askar-91f-flat-field-apo-91mm-f-6-7","title":"Askar 91F – Rifrattore Apocromatico Flat-Field 91mm f\/6.7 Quadruplet APO","description":"\u003cdiv style=\"font-family: Arial, sans-serif; font-size: 16px; line-height: 1.7; color: #333;\" class=\"product-description\"\u003e\n\n\u003ch1 style=\"font-size: 24px; font-weight: bold;\"\u003eAskar 91F – Rifrattore apocromatico quadrupletto Flat-Field 91\/609 mm f\/6,7\u003c\/h1\u003e\n\n\u003cp style=\"font-size: 18px; margin-top: 10px;\"\u003e\nL’\u003cstrong\u003eAskar 91F\u003c\/strong\u003e è un \u003cstrong\u003erifrattore apocromatico quadrupletto a campo piano\u003c\/strong\u003e, progettato per offrire un sistema ottico completo e immediatamente utilizzabile sia per l’\u003cstrong\u003eastrofotografia deep sky\u003c\/strong\u003e sia per l’\u003cstrong\u003eosservazione visuale\u003c\/strong\u003e. Dispone di un’apertura di \u003cstrong\u003e91 mm\u003c\/strong\u003e, una lunghezza focale di \u003cstrong\u003e609 mm\u003c\/strong\u003e e un rapporto focale nativo di \u003cstrong\u003ef\/6,7\u003c\/strong\u003e.\n\u003c\/p\u003e\n\n\u003cp\u003e\nLo schema ottico è composto da \u003cstrong\u003equattro elementi\u003c\/strong\u003e, tre anteriori e un elemento correttore posteriore, e comprende un vetro \u003cstrong\u003eED a bassa dispersione\u003c\/strong\u003e per limitare efficacemente l’aberrazione cromatica e ottenere immagini nitide, contrastate e ricche di dettagli.\n\u003c\/p\u003e\n\n\u003cp\u003e\nGrazie al correttore di campo integrato, l’Askar 91F offre un \u003cstrong\u003ecerchio d’immagine corretto da 44 mm\u003c\/strong\u003e, adatto anche a camere con sensore \u003cstrong\u003efull frame\u003c\/strong\u003e. Non è quindi necessario acquistare uno spianatore separato o rispettare un backfocus fotografico prestabilito: è sufficiente collegare la camera, raggiungere la corretta messa a fuoco e iniziare l’acquisizione.\n\u003c\/p\u003e\n\n\u003ch2 style=\"font-size: 20px; margin-top: 30px;\"\u003eOttica quadrupletto Flat-Field\u003c\/h2\u003e\n\n\u003cul style=\"margin-top: 15px; padding-left: 20px;\"\u003e\n\u003cli\u003eSchema ottico apocromatico a quattro elementi\u003c\/li\u003e\n\u003cli\u003eTre elementi anteriori e un correttore posteriore integrato\u003c\/li\u003e\n\u003cli\u003eElemento ottico ED per un’elevata correzione cromatica\u003c\/li\u003e\n\u003cli\u003eCampo piano senza necessità di uno spianatore aggiuntivo\u003c\/li\u003e\n\u003cli\u003eCerchio d’immagine corretto da 44 mm\u003c\/li\u003e\n\u003cli\u003eCompatibile con camere astronomiche e fotografiche full frame\u003c\/li\u003e\n\u003cli\u003eNessun backfocus fotografico prestabilito da calcolare\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2 style=\"font-size: 20px; margin-top: 30px;\"\u003eMeccanica precisa e versatile\u003c\/h2\u003e\n\n\u003cp\u003e\nIl telescopio è equipaggiato con un robusto \u003cstrong\u003efocheggiatore Rack \u0026amp; Pinion da 3\"\u003c\/strong\u003e, dotato di regolazione micrometrica con demoltiplica \u003cstrong\u003e1:10\u003c\/strong\u003e e una corsa di 30 mm. Il rotatore posteriore a \u003cstrong\u003e360° con scala graduata\u003c\/strong\u003e permette di orientare con precisione la camera e scegliere facilmente l’inquadratura desiderata.\n\u003c\/p\u003e\n\n\u003cp\u003e\nIl paraluce retrattile rende il tubo più compatto durante il trasporto, mentre il rivestimento interno opaco contribuisce a ridurre i riflessi e la luce diffusa. La maniglia superiore da 130 mm dispone di una sede per cercatore, affiancata da ulteriori punti di montaggio sui lati del focheggiatore per cercatori, telescopi guida e altri accessori.\n\u003c\/p\u003e\n\n\u003cul style=\"margin-top: 15px; padding-left: 20px;\"\u003e\n\u003cli\u003eFocheggiatore Rack \u0026amp; Pin da 3\"\u003c\/li\u003e\n\u003cli\u003eRegolazione micrometrica con demoltiplica 1:10\u003c\/li\u003e\n\u003cli\u003eRotatore fotografico a 360° con scala graduata\u003c\/li\u003e\n\u003cli\u003eParaluce retrattile\u003c\/li\u003e\n\u003cli\u003eManiglia superiore con sede per cercatore\u003c\/li\u003e\n\u003cli\u003eUlteriori basi laterali per il montaggio degli accessori\u003c\/li\u003e\n\u003cli\u003eAnelli lavorati CNC\u003c\/li\u003e\n\u003cli\u003eBarra a coda di rondine Vixen da 230 mm\u003c\/li\u003e\n\u003cli\u003eFori filettati da 1\/4\" e 3\/8\" per il collegamento a treppiedi\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2 style=\"font-size: 20px; margin-top: 30px;\"\u003eCollegamenti fotografici e visuali\u003c\/h2\u003e\n\n\u003cp\u003e\nL’Askar 91F viene fornito con adattatori fotografici filettati \u003cstrong\u003eM54×0,75\u003c\/strong\u003e e \u003cstrong\u003eM48×0,75\u003c\/strong\u003e. L’adattatore M48 integra inoltre una filettatura per filtri astronomici da \u003cstrong\u003e2\"\u003c\/strong\u003e. Per l’utilizzo visuale sono disponibili collegamenti compatibili con accessori da \u003cstrong\u003e2\"\u003c\/strong\u003e e \u003cstrong\u003e1,25\"\u003c\/strong\u003e.\n\u003c\/p\u003e\n\n\u003ch2 style=\"font-size: 20px; margin-top: 30px;\"\u003eSpecifiche tecniche\u003c\/h2\u003e\n\n\u003ctable style=\"width: 100%; border-collapse: collapse; margin-top: 10px;\"\u003e\n\u003ctbody\u003e\n\n\u003ctr\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003e\u003cstrong\u003eModello\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003eAskar 91F Flat-Field\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003ctr\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003e\u003cstrong\u003eTipologia\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003eRifrattore apocromatico quadrupletto a campo piano\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003ctr\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003e\u003cstrong\u003eSchema ottico\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003eQuattro elementi, tre anteriori e uno posteriore\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003ctr\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003e\u003cstrong\u003eVetro ottico\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003eUn elemento ED a bassa dispersione\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003ctr\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003e\u003cstrong\u003eDiametro\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003e91 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003ctr\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003e\u003cstrong\u003eLunghezza focale\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003e609 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003ctr\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003e\u003cstrong\u003eRapporto focale\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003ef\/6,7\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003ctr\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003e\u003cstrong\u003eCerchio d’immagine\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003e44 mm, compatibile con sensori full frame\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003ctr\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003e\u003cstrong\u003eCorrettore di campo\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003eIntegrato\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003ctr\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003e\u003cstrong\u003eBackfocus fotografico\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003eNessuna distanza prestabilita da rispettare\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003ctr\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003e\u003cstrong\u003eFocheggiatore\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003eRack \u0026amp; Pinion da 3\", doppia velocità 1:10\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003ctr\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003e\u003cstrong\u003eCorsa del focheggiatore\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003e30 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003ctr\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003e\u003cstrong\u003eRotatore\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003e360° con scala graduata\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003ctr\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003e\u003cstrong\u003eConnessioni fotografiche\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003eM54×0,75 e M48×0,75\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003ctr\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003e\u003cstrong\u003eFilettatura filtri\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003e2\" integrata nell’adattatore M48\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003ctr\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003e\u003cstrong\u003eConnessioni visuali\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003e2\" e 1,25\"\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003ctr\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003e\u003cstrong\u003eParaluce\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003eRetrattile\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003ctr\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003e\u003cstrong\u003eLunghezza con adattatore fotografico\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003e550 mm con paraluce retratto; 636 mm con paraluce esteso\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003ctr\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003e\u003cstrong\u003ePeso tubo ottico\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003e3,92 kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003ctr\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003e\u003cstrong\u003ePeso con anelli, maniglia e barra\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003e4,52 kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003ctr\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003e\u003cstrong\u003eBarra a coda di rondine\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding: 8px; border: 1px solid #ccc;\"\u003eVixen da 230 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2 style=\"font-size: 20px; margin-top: 30px;\"\u003eContenuto della confezione\u003c\/h2\u003e\n\n\u003cul style=\"margin-top: 15px; padding-left: 20px;\"\u003e\n\u003cli\u003eTubo ottico Askar 91F\u003c\/li\u003e\n\u003cli\u003eCoppia di anelli di supporto\u003c\/li\u003e\n\u003cli\u003eManiglia superiore\u003c\/li\u003e\n\u003cli\u003eBarra a coda di rondine Vixen da 230 mm\u003c\/li\u003e\n\u003cli\u003eSet di adattatori fotografici\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cdiv style=\"background-color: #f0f8ff; padding: 15px; margin-top: 30px; border-left: 4px solid #007acc;\"\u003e\n\u003cstrong\u003eSpedizione gratuita in Italia\u003c\/strong\u003e\u003cbr\u003e\nI prodotti con un costo superiore a \u003cstrong\u003e199,99 €\u003c\/strong\u003e prevedono la \u003cstrong\u003espedizione gratuita\u003c\/strong\u003e.\n\u003c\/div\u003e\n\n\u003c\/div\u003e","brand":"Askar","offers":[{"title":"Default Title","offer_id":51121384259800,"sku":"ASK-91f","price":1099.0,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0766\/0722\/6072\/files\/askar91fgikordanophoto.png?v=1764084132","url":"https:\/\/www.giordanoastronomia.it\/products\/askar-91f-flat-field-apo-91mm-f-6-7","provider":"Giordano Astronomia","version":"1.0","type":"link"}