{"id":34224,"date":"2025-11-17T15:31:39","date_gmt":"2025-11-17T14:31:39","guid":{"rendered":"https:\/\/www.telescoop.nl\/?post_type=product&#038;p=34224"},"modified":"2026-07-20T14:20:45","modified_gmt":"2026-07-20T12:20:45","slug":"william-optics-flat-gt-flattener-gran-turismo-refractor-2-inch","status":"publish","type":"product","link":"https:\/\/www.telescoop.nl\/en\/william-optics-flat-gt-flattener-gran-turismo-refractor-2-inch\/","title":{"rendered":"William Optics Flat GT Flattener for GranTurismo Refractor"},"content":{"rendered":"<h2 class=\"wp-block-heading has-text-align-center\"><strong>William Optics Flat GT Flattener voor GranTurismo Refractor: de berekende flattener voor je GranTurismo<\/strong><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">De William Optics Flat GT is de beeldveldvlakker voor de GranTurismo 71 en 81 apochromaten. Elke refractor levert van nature een licht gebogen beeldvlak; een vlakke camerasensor snijdt daar doorheen, waardoor sterren in de hoeken uitrekken tot streepjes. Een flattener rekent die kromming weg, zodat sterren tot in de hoeken klein en rond blijven. De correctie is berekend tot en met full-frame sensoren, belangrijk bij deze snelle refractors (f\/5 tot f\/7).<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Met een lengte van slechts 22 mm (0,9 inch) en twee lenselementen in een groep blijft de trein kort, licht en stijf. De meegeleverde afstandsring zet de flattener op de juiste positie voor de GT71 en GT81.<\/p>\n\n\n\n<figure class=\"wp-block-gallery has-nested-images columns-3 is-cropped wp-block-gallery-1 is-layout-flex wp-block-gallery-is-layout-flex\"><figure class=\"wp-block-image\"><img decoding=\"async\" src=\"https:\/\/www.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-Flat-GT-1.jpg\" alt=\"William Optics Flat GT flattener voor GranTurismo\" title=\"\"><\/figure><figure class=\"wp-block-image\"><img decoding=\"async\" src=\"https:\/\/www.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-Flat-GT-4.jpg\" alt=\"William Optics Flat GT flattener voor GranTurismo\" title=\"\"><\/figure><figure class=\"wp-block-image\"><img decoding=\"async\" src=\"https:\/\/www.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-Flat-GT-5.jpg\" alt=\"William Optics Flat GT flattener voor GranTurismo\" title=\"\"><\/figure><figure class=\"wp-block-image\"><img decoding=\"async\" src=\"https:\/\/www.telescoop.nl\/wp-content\/uploads\/2025\/11\/1.jpg\" alt=\"William Optics Flat GT flattener voor GranTurismo\" title=\"\"><\/figure><figure class=\"wp-block-image\"><img decoding=\"async\" src=\"https:\/\/www.telescoop.nl\/wp-content\/uploads\/2025\/11\/2.jpg\" alt=\"William Optics Flat GT flattener voor GranTurismo\" title=\"\"><\/figure><figure class=\"wp-block-image\"><img decoding=\"async\" src=\"https:\/\/www.telescoop.nl\/wp-content\/uploads\/2025\/11\/3.jpg\" alt=\"William Optics Flat GT flattener voor GranTurismo\" title=\"\"><\/figure><figure class=\"wp-block-image\"><img decoding=\"async\" src=\"https:\/\/www.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-Flat-GT-3.jpg\" alt=\"William Optics Flat GT flattener voor GranTurismo\" title=\"\"><\/figure><\/figure>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-8d39b2df wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:38%\">\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" src=\"https:\/\/www.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-Flat-GT-4.jpg\" alt=\"William Optics Flat GT flattener voor GranTurismo\" title=\"\"><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:62%\">\n<h4 class=\"wp-block-heading\">De juiste sensorafstand<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">Plaats je camera op ongeveer 55 mm achter de flattener: de standaardbackfocus waar de William Optics M48-adapters en 48 mm T-ringen precies op uitkomen. De M48-camerazijde heeft een geintegreerde filterdraad.<\/p>\n<\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-8d39b2df wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:38%\">\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" src=\"https:\/\/www.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-Flat-GT-5.jpg\" alt=\"William Optics Flat GT flattener voor GranTurismo\" title=\"\"><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:62%\">\n<h4 class=\"wp-block-heading\">Backfocus tekort?<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">Kom je in jouw configuratie lengte tekort, dan brengt het William Optics verlengstuk voor de Flat GT de trein alsnog op maat.<\/p>\n<\/div>\n<\/div>\n\n\n\n<h3 class=\"wp-block-heading\">Featured accessories<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Sluit je camera aan met de M48-adapter voor jouw bajonet; het Flat GT-verlengstuk lost een backfocustekort op.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">For whom yes and for whom no<\/h3>\n\n\n\n<ul class=\"wp-block-list\"><li>\u2713 Bezitters van een GranTurismo 71 of 81 die fotograferen<\/li><li>\u2713 Full-frame fotografen op een snelle apo<\/li><li>\u2717 Bezitters van de ZenithStar-serie: daarvoor zijn de Flat61R en Flat73A berekend<\/li><\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Specifications<\/h3>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td><strong>Type<\/strong><\/td><td>Field of view flattener<\/td><\/tr><tr><td><strong>Suitable for<\/strong><\/td><td>William Optics GranTurismo 71 en 81<\/td><\/tr><tr><td><strong>Image circle<\/strong><\/td><td>Full-frame<\/td><\/tr><tr><td><strong>Optics<\/strong><\/td><td>2 elementen in 1 groep<\/td><\/tr><tr><td><strong>Length<\/strong><\/td><td>22 mm (0,9 inch)<\/td><\/tr><tr><td><strong>Telescope silk<\/strong><\/td><td>M63<\/td><\/tr><tr><td><strong>Camera side<\/strong><\/td><td>M48, met geintegreerde filterdraad<\/td><\/tr><tr><td><strong>Aanbevolen backfocus<\/strong><\/td><td>ca. 55 mm<\/td><\/tr><tr><td><strong>Included<\/strong><\/td><td>Afstandsring<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">You can find more accessories for this merk at the <a href=\"\/en\/brands\/william-optics\/\">William Optics merk Page<\/a>.<\/p>","protected":false},"excerpt":{"rendered":"<p>William Optics Flat GT flattener voor de GranTurismo 71 en 81: M63-telescoopzijde, M48-camerazijde met filterdraad, full-frame correctie en slechts 22 mm lang.<\/p>","protected":false},"featured_media":97628,"comment_status":"open","ping_status":"closed","template":"","meta":{"_acf_changed":false},"product_brand":[643],"product_cat":[56,469,3107,3105,589,3104,592],"product_tag":[],"class_list":["post-34224","product","type-product","status-publish","has-post-thumbnail","product_brand-william-optics","product_cat-telescoop-accessoires","product_cat-astro-fotografie","product_cat-flatteners","product_cat-optische-accessoires","product_cat-optische-accessoires-v1","product_cat-overige-astrofotografie-accessoires","product_cat-reducers-flatteners","product_shipping_class-licht","first","instock","taxable","shipping-taxable","purchasable","product-type-simple"],"bundled_by":[],"bundle_stock_status":"instock","bundle_stock_quantity":null,"bundle_virtual":false,"bundle_layout":"","bundle_add_to_cart_form_location":"","bundle_editable_in_cart":false,"bundle_sold_individually_context":"","bundle_item_grouping":"","bundle_min_size":"","bundle_max_size":"","bundle_price":[],"bundled_items":[],"bundle_sell_ids":[33986],"acf":[],"jetpack_sharing_enabled":true,"jetpack-related-posts":[{"id":33813,"url":"https:\/\/www.telescoop.nl\/en\/william-optics-granturismo-71-420-apo-ota\/","url_meta":{"origin":34224,"position":0},"title":"William Optics GranTurismo 71\/420 APO OTA","author":"","date":"14-11-2025","format":false,"excerpt":"William Optics GranTurismo 71: FPL-53 triplet apochromaat 71\/420 f\/5,9 met 2,5 inch rack-and-pinion focuser (1:10). 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