{"id":33813,"date":"2025-11-14T17:49:28","date_gmt":"2025-11-14T16:49:28","guid":{"rendered":"https:\/\/www.telescoop.nl\/?post_type=product&#038;p=33813"},"modified":"2026-03-04T17:09:03","modified_gmt":"2026-03-04T16:09:03","slug":"william-optics-granturismo-71-420-apo-ota","status":"publish","type":"product","link":"https:\/\/staging.telescoop.nl\/en\/william-optics-granturismo-71-420-apo-ota\/","title":{"rendered":"William Optics GranTurismo 71\/420 APO OTA"},"content":{"rendered":"<h3 class=\"wp-block-heading\">Compact, bright and made for perfect constellations<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The William Optics AP 71\/420 GT 71 is small in size, but big in performance.You get a bright, clean and colorful image without distracting edges. The triplet lens with FPL-53 glass keeps colors together neatly, keeping stars point-shaped. This makes your photos calmer, sharper and much easier to edit.<\/p>\n\n\n\n<figure class=\"wp-block-gallery has-nested-images columns-default is-cropped wp-block-gallery-1 is-layout-flex wp-block-gallery-is-layout-flex\">\n<figure class=\"wp-block-image aligncenter size-large\"><img decoding=\"async\" data-id=\"33814\" src=\"https:\/\/staging.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-AP-71-420-GT-71-Apochromatische-refractor-Gran-Turismo-2.jpg\" alt=\"William Optics AP 71\/420 GT 71 front view with open dew cap and integrated Bahtinov mask\" class=\"wp-image-33814\" title=\"\"><\/figure>\n<\/figure>\n\n\n\n<h3 class=\"wp-block-heading\">For those who like to travel and want sharp images<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The GT 71 is light, short and sturdily built. You lift it easily, take it with you without fuss, and set it up in a minute.Under dark skies, you immediately see what this little apo can do: bright star clusters, fine details on the Moon, and a surprising amount of deep-sky.The high contrast reproduction makes planets calm and sharp, and shows structure that is often missed with smaller lenses.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Made for astrophotography<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">You get a nice flat image, so your camera exposes the entire frame evenly. Full-frame also works fine.<br>Use the William Optics Flat6AIII flattener\/reducer and you get an even faster system. Ideal if you like to shoot short exposure times or if you work under light sky areas.The focuser is strong, smooth and precise. Heavy camera? No problem. You focus without jerking, and you can rotate the whole camera for better framing.<\/p>\n\n\n\n<figure class=\"wp-block-gallery has-nested-images columns-default is-cropped wp-block-gallery-2 is-layout-flex wp-block-gallery-is-layout-flex\">\n<figure class=\"wp-block-image aligncenter size-large\"><img decoding=\"async\" data-id=\"33815\" src=\"https:\/\/staging.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-AP-71-420-GT-71-Apochromatische-refractor-Gran-Turismo-3.jpg\" alt=\"William Optics AP 71\/420 GT 71 rear view with 2.5-inch R&amp;P focuser and fine adjustment\" class=\"wp-image-33815\" title=\"\"><\/figure>\n<\/figure>\n\n\n\n<h3 class=\"wp-block-heading\">Smart details that make your job easier<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The handle incorporates a Vixen-style dovetail so you can easily insert a guidescope.<br>The Bahtinov mask helps you focus super fast. The clear acrylic lets a lot of light through, so you can focus even on faint stars.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">This is why the GT 71 feels so comfortable<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">He works directly. He behaves stably.<br>And above all, he provides images that make you curious for more.<br>For those who want mobile photography and still want top quality, this is a reliable all-rounder that you can use for years without any problems.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Specifications<\/h3>\n\n\n\n<h4 class=\"wp-block-heading\">Optics<\/h4>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>Feature<\/th><th>Description<\/th><\/tr><\/thead><tbody><tr><td>Type<\/td><td>Refractor<\/td><\/tr><tr><td>Design<\/td><td>Apochromat<\/td><\/tr><tr><td>Aperture (mm)<\/td><td>71<\/td><\/tr><tr><td>Focal length (mm)<\/td><td>420<\/td><\/tr><tr><td>Focal Ratio (f\/)<\/td><td>5,9<\/td><\/tr><tr><td>Resolution (\u2033)<\/td><td>1,94<\/td><\/tr><tr><td>Limit value (mag)<\/td><td>11,1<\/td><\/tr><tr><td>Light output<\/td><td>100<\/td><\/tr><tr><td>Max. useful magnification<\/td><td>142\u00d7<\/td><\/tr><tr><td>Lens Design<\/td><td>Triplet<\/td><\/tr><tr><td>Coating<\/td><td>SMC multilayer coating<\/td><\/tr><tr><td>Field of view (mm)<\/td><td>44<\/td><\/tr><tr><td>Tube weight (kg)<\/td><td>2,2<\/td><\/tr><tr><td>Tube diameter (mm)<\/td><td>82<\/td><\/tr><tr><td>Tube length (mm)<\/td><td>427<\/td><\/tr><tr><td>Transport length (mm)<\/td><td>325<\/td><\/tr><tr><td>Dew cap diameter (mm)<\/td><td>92<\/td><\/tr><tr><td>Scatter light baffle<\/td><td>Yes<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<h4 class=\"wp-block-heading\">Focuser<\/h4>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>Feature<\/th><th>Description<\/th><\/tr><\/thead><tbody><tr><td>Design<\/td><td>Rack &amp; Pinion<\/td><\/tr><tr><td>Ocular connection<\/td><td>2\u2033<\/td><\/tr><tr><td>Free opening (mm)<\/td><td>64<\/td><\/tr><tr><td>Ring clamp<\/td><td>Yes<\/td><\/tr><tr><td>Reduction<\/td><td>1:10 fine adjustment<\/td><\/tr><tr><td>Rotatable<\/td><td>Yes<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<h4 class=\"wp-block-heading\">Mount<\/h4>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>Feature<\/th><th>Description<\/th><\/tr><\/thead><tbody><tr><td>Design<\/td><td>OTA<\/td><\/tr><tr><td>Type of mount<\/td><td>Without mount<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<h4 class=\"wp-block-heading\">Included accessories<\/h4>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>Section<\/th><th>Description<\/th><\/tr><\/thead><tbody><tr><td>Dew cap<\/td><td>Yes<\/td><\/tr><tr><td>Eyepiece adapter<\/td><td>2\u2033 \/ 1,25\u2033<\/td><\/tr><tr><td>Dovetail<\/td><td>Vixen-Style<\/td><\/tr><tr><td>Handle<\/td><td>Yes<\/td><\/tr><tr><td>Transport bag<\/td><td>Yes<\/td><\/tr><tr><td>Focusing aid<\/td><td>Bahtinov mask<\/td><\/tr><tr><td>Miscellaneous<\/td><td>Image field rotator<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<h4 class=\"wp-block-heading\">General<\/h4>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>Feature<\/th><th>Description<\/th><\/tr><\/thead><tbody><tr><td>Series<\/td><td>Gran Turismo<\/td><\/tr><tr><td>Color<\/td><td>Red<\/td><\/tr><tr><td>Application<\/td><td>Astrophotography (very good), Moon &amp; Planets, Nebulae &amp; Galaxies<\/td><\/tr><tr><td>Sun<\/td><td>No (only with appropriate filters)<\/td><\/tr><tr><td>Recommended for<\/td><td>Advanced<\/td><\/tr><tr><td>Observatory<\/td><td>No<\/td><\/tr><\/tbody><\/table><\/figure>","protected":false},"excerpt":{"rendered":"<p>William Optics AP 71\/420 GT 71 comes with Bahtinov focus mask, 2.5\u2033 R&amp;P focuser with 1:10 reduction, 2\u2033\/1.25\u2033 adapter, Vixen swallowtail, carrying handle and padded transport bag - perfect for sharp astrophotos and visual observation on the go. \u00a0<\/p>","protected":false},"featured_media":97321,"comment_status":"open","ping_status":"closed","template":"","meta":{"_acf_changed":false},"product_brand":[643],"product_cat":[51,567],"product_tag":[],"class_list":["post-33813","product","type-product","status-publish","has-post-thumbnail","product_brand-william-optics","product_cat-telescopen","product_cat-refractors","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":[],"acf":[],"jetpack_sharing_enabled":true,"jetpack-related-posts":[{"id":33699,"url":"https:\/\/staging.telescoop.nl\/en\/william-optics-ap-71-350-71-apochromatische-refractor-redcat-wifd\/","url_meta":{"origin":33813,"position":0},"title":"William Optics AP 71\/350 71 Apochromatic refractor RedCat WIFD","author":"","date":"14-11-2025","format":false,"excerpt":"William Optics AP 71\/350 71 wordt geleverd met een beschermende nylon draagtas, een in de objectiefkap ingebouwd Bahtinov-masker voor perfecte scherpstelling, en een veelzijdige Arca-Swiss & Vixen-Style zwaluwstaart voor eenvoudige montage. \u00a0","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/staging.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-AP-71-350-71-Apochromatische-refractor-RedCat-WIFD-1.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/staging.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-AP-71-350-71-Apochromatische-refractor-RedCat-WIFD-1.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/staging.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-AP-71-350-71-Apochromatische-refractor-RedCat-WIFD-1.jpg?resize=525%2C300&ssl=1 1.5x, https:\/\/i0.wp.com\/staging.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-AP-71-350-71-Apochromatische-refractor-RedCat-WIFD-1.jpg?resize=700%2C400&ssl=1 2x"},"classes":[]},{"id":33684,"url":"https:\/\/staging.telescoop.nl\/en\/william-optics-ap-71-350-71-apochromatische-refractor-redcat-ota\/","url_meta":{"origin":33813,"position":1},"title":"William Optics AP 71\/350 71 Apochromatic refractor RedCat OTA","author":"","date":"14-11-2025","format":false,"excerpt":"William Optics AP 71\/350 71 comes with a protective nylon carrying case, a Vixen\/Arca-Swiss dovetail and a Bahtinov mask integrated into the objective cap - ideal for astrophotographers who want perfect focus and portability. \u00a0","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/staging.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-AP-71-350-71-Apochromatische-refractor-RedCat-OTA-1.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/staging.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-AP-71-350-71-Apochromatische-refractor-RedCat-OTA-1.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/staging.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-AP-71-350-71-Apochromatische-refractor-RedCat-OTA-1.jpg?resize=525%2C300&ssl=1 1.5x, https:\/\/i0.wp.com\/staging.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-AP-71-350-71-Apochromatische-refractor-RedCat-OTA-1.jpg?resize=700%2C400&ssl=1 2x"},"classes":[]},{"id":34224,"url":"https:\/\/staging.telescoop.nl\/en\/william-optics-flat-gt-flattener-gran-turismo-refractor-2-inch\/","url_meta":{"origin":33813,"position":2},"title":"William Optics Flat GT Flattener for GranTurismo Refractor","author":"","date":"17-11-2025","format":false,"excerpt":"William Optics Flat GT comes with M63 telescope mount, M48 camera thread, integrated filter thread, 2-element optics, full-frame correction and distance ring for GT71 and GT81 - for sharp stars all the way to the image edge.","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/staging.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-Flat-GT-1.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/staging.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-Flat-GT-1.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/staging.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-Flat-GT-1.jpg?resize=525%2C300&ssl=1 1.5x, https:\/\/i0.wp.com\/staging.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-Flat-GT-1.jpg?resize=700%2C400&ssl=1 2x"},"classes":[]},{"id":34116,"url":"https:\/\/staging.telescoop.nl\/en\/william-optics-71-73-zenithstar-transporttas\/","url_meta":{"origin":33813,"position":3},"title":"William Optics 71 &amp; 73 ZenithStar Transport Bag","author":"","date":"17-11-2025","format":false,"excerpt":"William Optics 71 & 73 wordt geleverd met stevige buitenkant, ritssluiting en handgrepen \u2013 ontworpen om het originele schuimrubberen inzetstuk van je ZenithStar-telescoop veilig te vervoeren.","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/staging.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-71-73-ZenithStar-Transporttas.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/staging.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-71-73-ZenithStar-Transporttas.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/staging.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-71-73-ZenithStar-Transporttas.jpg?resize=525%2C300&ssl=1 1.5x, https:\/\/i0.wp.com\/staging.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-71-73-ZenithStar-Transporttas.jpg?resize=700%2C400&ssl=1 2x"},"classes":[]},{"id":33986,"url":"https:\/\/staging.telescoop.nl\/en\/william-optics-4-verlengstuk-voor-flat-gt\/","url_meta":{"origin":33813,"position":4},"title":"William Optics 4 Extension for Flat GT","author":"","date":"16-11-2025","format":false,"excerpt":"William Optics 4 Extension for Flat GT comes as an essential 67mm extension tube with M92 thread, specially designed to achieve proper back focus for astrophotography with the Flat GT flattener. \u00a0","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/staging.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-4-Verlengstuk-voor-Flat-GT-1.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/staging.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-4-Verlengstuk-voor-Flat-GT-1.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/staging.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-4-Verlengstuk-voor-Flat-GT-1.jpg?resize=525%2C300&ssl=1 1.5x, https:\/\/i0.wp.com\/staging.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-4-Verlengstuk-voor-Flat-GT-1.jpg?resize=700%2C400&ssl=1 2x"},"classes":[]},{"id":92575,"url":"https:\/\/staging.telescoop.nl\/en\/omegon-pro-apo-ap-71-490-quadruplet-ota\/","url_meta":{"origin":33813,"position":5},"title":"Omegon Pro APO AP 71\/490 Quadruplet OTA - 71mm Refractor","author":"Info telescoop","date":"06-01-2026","format":false,"excerpt":"Omegon Pro AP 71\/490 Refractor\u00a0wordt geleverd met ge\u00efntegreerde field flattener, 2,5\" focuser met 1:10 reductie, ringklemmen, Vixen-style zwaluwstaart, Amici-prisma (1,25\u201d), 8mm & 20mm oculairen \u2013 ideaal voor gevorderde astrofotografen die hoge beeldkwaliteit wensen met vlak beeldveld.","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/staging.telescoop.nl\/wp-content\/uploads\/2026\/01\/Omegon-apochromatische-refractor-Pro-APO-AP-71-490-Quadruplet-OTA-9.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/staging.telescoop.nl\/wp-content\/uploads\/2026\/01\/Omegon-apochromatische-refractor-Pro-APO-AP-71-490-Quadruplet-OTA-9.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/staging.telescoop.nl\/wp-content\/uploads\/2026\/01\/Omegon-apochromatische-refractor-Pro-APO-AP-71-490-Quadruplet-OTA-9.jpg?resize=525%2C300&ssl=1 1.5x, https:\/\/i0.wp.com\/staging.telescoop.nl\/wp-content\/uploads\/2026\/01\/Omegon-apochromatische-refractor-Pro-APO-AP-71-490-Quadruplet-OTA-9.jpg?resize=700%2C400&ssl=1 2x"},"classes":[]}],"_links":{"self":[{"href":"https:\/\/staging.telescoop.nl\/en\/wp-json\/wp\/v2\/product\/33813","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/staging.telescoop.nl\/en\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/staging.telescoop.nl\/en\/wp-json\/wp\/v2\/types\/product"}],"replies":[{"embeddable":true,"href":"https:\/\/staging.telescoop.nl\/en\/wp-json\/wp\/v2\/comments?post=33813"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/staging.telescoop.nl\/en\/wp-json\/wp\/v2\/media\/97321"}],"wp:attachment":[{"href":"https:\/\/staging.telescoop.nl\/en\/wp-json\/wp\/v2\/media?parent=33813"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/staging.telescoop.nl\/en\/wp-json\/wp\/v2\/product_brand?post=33813"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/staging.telescoop.nl\/en\/wp-json\/wp\/v2\/product_cat?post=33813"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/staging.telescoop.nl\/en\/wp-json\/wp\/v2\/product_tag?post=33813"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}