{"id":33829,"date":"2025-11-15T12:17:44","date_gmt":"2025-11-15T11:17:44","guid":{"rendered":"https:\/\/www.telescoop.nl\/?post_type=product&#038;p=33829"},"modified":"2026-03-04T17:08:24","modified_gmt":"2026-03-04T16:08:24","slug":"william-optics-granturismo-81-478-apo-iv-gold-ota","status":"publish","type":"product","link":"https:\/\/staging.telescoop.nl\/en\/william-optics-granturismo-81-478-apo-iv-gold-ota\/","title":{"rendered":"William Optics GranTurismo 81\/478 APO IV Gold OTA"},"content":{"rendered":"<h3 class=\"wp-block-heading\">William Optics AP 81\/478 81 - Compact, bright and made for sharp astrophotos<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">You choose the <strong>William Optics AP 81\/478 81<\/strong> if you want a lightweight, travel-friendly telescope that still delivers images with true premium quality.The triplet design with top-quality glass keeps colors together neatly, keeping your photos calm, clear and razor-sharp. You can immediately see why this series is so popular: everything feels stable, precise and designed for real photographers.<\/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=\"33830\" src=\"https:\/\/staging.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-AP-81-478-81-Apochromatische-refractor-Gran-Turismo-IV-OTA-2.jpg\" alt=\"William Optics AP 81\/478 81 telescope in gold finish with objective cap and Bahtinov mask\" class=\"wp-image-33830\" title=\"\"><\/figure>\n<\/figure>\n\n\n\n<h3 class=\"wp-block-heading\">Clear image across the entire frame<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The 81 mm aperture provides enough light for sharp shots of nebulae, star fields and bright deep-sky objects.The short focal length feels fast. You take wide sky photos with lots of detail, without the hassle of long exposure times.It also works pleasant visually: the Moon, planets and star clusters show nice contrast and tight edges.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Color clean and sleek, so your photos succeed better<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The apochromatic triplet ensures that bright stars do not get purple edges. With a good flattener\/reducer such as the William Optics Flat6AIII you make the image perfectly flat, even for full-frame cameras. Useful if you want to take advantage of every pixel.<\/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=\"33834\" src=\"https:\/\/staging.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-AP-81-478-81-Apochromatische-refractor-Gran-Turismo-IV-OTA-1.jpg\" alt=\"William Optics AP 81\/478 81 available in different colors\" class=\"wp-image-33834\" title=\"\"><\/figure>\n<\/figure>\n\n\n\n<h3 class=\"wp-block-heading\">Stable focus that stays put<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The sturdy focuser works accurately and keeps your camera straight, even if you use some heavier equipment.The 1:10 micro fine adjustment helps you take that exact last little step for sharp stars.Focusing is easy, especially with the integrated Bahtinov mask. You slide the mask on, focus and can start recording immediately.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Smartly built for photographers<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The tube is light but sturdy, ideal for travel or a quick session in the garden.You get a handle with built-in dovetail, so you can fit a guidescope without extra parts. This makes your setup easier AND more stable.Everything feels well thought out: strong housing, smooth focuser, handy accessories. You can tell this telescope is made to be used often.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Reliable under any sky<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The Gran Turismo series is known for its stable optics. The tube stays at a good temperature and gives a tight image even in changing weather.Take it to a dark place and you will immediately see why this telescope is loved by advanced users.<\/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>81<\/td><\/tr><tr><td>Focal length (mm)<\/td><td>478<\/td><\/tr><tr><td>Aperture ratio (f\/)<\/td><td>5,9<\/td><\/tr><tr><td>Resolution<\/td><td>1,70\u2033<\/td><\/tr><tr><td>Limit value (mag)<\/td><td>11,3<\/td><\/tr><tr><td>Light output<\/td><td>130<\/td><\/tr><tr><td>Max. useful magnification<\/td><td>162\u00d7<\/td><\/tr><tr><td>Tube weight (kg)<\/td><td>3,9<\/td><\/tr><tr><td>Tube length (mm)<\/td><td>460<\/td><\/tr><tr><td>Transport length (mm)<\/td><td>390<\/td><\/tr><tr><td>Coating<\/td><td>SMC multilayer coating<\/td><\/tr><tr><td>Stray light baffles<\/td><td>Yes<\/td><\/tr><tr><td>Lens Design<\/td><td>Triplet<\/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-and-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>Motorized<\/td><td>No<\/td><\/tr><tr><td>Ring clamp<\/td><td>Yes<\/td><\/tr><tr><td>Reduction<\/td><td>1:10 fine adjustment<\/td><\/tr><tr><td>Connection (telescope side)<\/td><td>M63<\/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>Seeker<\/td><td>No<\/td><\/tr><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>Miscellaneous<\/td><td>Bahtinov mask<\/td><\/tr><tr><td>Handle<\/td><td>Yes<\/td><\/tr><tr><td>Transport bag<\/td><td>Yes<\/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>Gold<\/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 safe filter)<\/td><\/tr><tr><td>Recommended for<\/td><td>Advanced<\/td><\/tr><tr><td>Observatory use<\/td><td>No<\/td><\/tr><\/tbody><\/table><\/figure>","protected":false},"excerpt":{"rendered":"<p>William Optics AP 81\/478 81 comes with a Vixen-Style dovetail, handle, Bahtinov mask, 2\u2033 to 1.25\u2033 adapter and a soft carrying case, ideal for mobile astrophotography. \u00a0<\/p>","protected":false},"featured_media":97327,"comment_status":"open","ping_status":"closed","template":"","meta":{"_acf_changed":false},"product_brand":[643],"product_cat":[51,567],"product_tag":[],"class_list":["post-33829","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":33849,"url":"https:\/\/staging.telescoop.nl\/en\/william-optics-granturismo-81-478-apo-wifd-ota\/","url_meta":{"origin":33829,"position":0},"title":"William Optics GranTurismo 81\/478 APO WIFD OTA","author":"","date":"15-11-2025","format":false,"excerpt":"William Optics AP 81\/478 81 comes with an internal WIFD focuser, Vixen-Style dovetail, handle, built-in field rotator, Bahtinov mask and a soft carrying case. \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-81-478-81-Apochromatische-refractor-GranTurismo-WIFD-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-81-478-81-Apochromatische-refractor-GranTurismo-WIFD-OTA-1.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/staging.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-AP-81-478-81-Apochromatische-refractor-GranTurismo-WIFD-OTA-1.jpg?resize=525%2C300&ssl=1 1.5x, 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GranTurismo 81\/478 APO IV OTA Red","author":"","date":"15-11-2025","format":false,"excerpt":"William Optics AP 81\/478 81 comes with a Vixen-Style dovetail, handle, Bahtinov mask, 2\" to 1.25\" adapter and a soft carrying case, ideal for mobile astrophotography. \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-81-478-81-Apochromatische-refractor-Gran-Turismo-IV-OTAWilliam-Optics-AP-81478-81-Apochromatische-refractor-Gran-Turismo-IV-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-81-478-81-Apochromatische-refractor-Gran-Turismo-IV-OTAWilliam-Optics-AP-81478-81-Apochromatische-refractor-Gran-Turismo-IV-OTA-1.jpg?resize=350%2C200&ssl=1 1x, 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\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-81-559-81-Apochromatische-refractor-ZenithStar-WIFD-Red-OTA-2.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-81-559-81-Apochromatische-refractor-ZenithStar-WIFD-Red-OTA-2.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/staging.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-AP-81-559-81-Apochromatische-refractor-ZenithStar-WIFD-Red-OTA-2.jpg?resize=525%2C300&ssl=1 1.5x, https:\/\/i0.wp.com\/staging.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-AP-81-559-81-Apochromatische-refractor-ZenithStar-WIFD-Red-OTA-2.jpg?resize=700%2C400&ssl=1 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