{"id":34300,"date":"2025-11-17T18:26:31","date_gmt":"2025-11-17T17:26:31","guid":{"rendered":"https:\/\/www.telescoop.nl\/?post_type=product&#038;p=34300"},"modified":"2026-08-25T15:11:45","modified_gmt":"2026-08-25T13:11:45","slug":"william-optics-flat73a-flattener-for-zenithstar-73","status":"publish","type":"product","link":"https:\/\/www.telescoop.nl\/en\/william-optics-flat73a-flattener-voor-zenithstar-73\/","title":{"rendered":"William Optics Flat73A Flattener for ZenithStar 73"},"content":{"rendered":"<h2 class=\"wp-block-heading has-text-align-center\"><strong>William Optics Flat73A Flattener for ZenithStar 73: the calculated flattener for your ZenithStar 73<\/strong><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The William Optics Flat73A is the field flattener designed for the ZenithStar 73. Every refractor naturally produces a slightly curved field of focus; a flat camera sensor cuts through this, causing stars in the corners to stretch into streaks. A flattener corrects this curvature, ensuring stars remain small and round all the way to the corners. Especially with this fast doublet and larger sensors, the correction makes the difference between soft and sharp corners.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">You screw the flattener directly onto the focuser: no loose adapters, no wobbly clamp connection. The scale-marked adjustment ring sets the backfocus; once found, you dial in the same value each session.<\/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-Flattener-Flat73A-voor-ZenithStar-73-5.jpg\" alt=\"William Optics Flat73A Flattener for ZenithStar 73\" title=\"\"><\/figure><figure class=\"wp-block-image\"><img decoding=\"async\" src=\"https:\/\/www.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-Flattener-Flat73A-voor-ZenithStar-73-4.jpg\" alt=\"William Optics Flat73A Flattener for ZenithStar 73\" title=\"\"><\/figure><figure class=\"wp-block-image\"><img decoding=\"async\" src=\"https:\/\/www.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-Flattener-Flat73A-voor-ZenithStar-73-3.jpg\" alt=\"William Optics Flat73A Flattener for ZenithStar 73\" title=\"\"><\/figure><figure class=\"wp-block-image\"><img decoding=\"async\" src=\"https:\/\/www.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-Flattener-Flat73A-voor-ZenithStar-73-2.jpg\" alt=\"William Optics Flat73A Flattener for ZenithStar 73\" title=\"\"><\/figure><figure class=\"wp-block-image\"><img decoding=\"async\" src=\"https:\/\/www.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-Flattener-Flat73A-voor-ZenithStar-73-1.jpg\" alt=\"William Optics Flat73A Flattener for ZenithStar 73\" title=\"\"><\/figure><figure class=\"wp-block-image\"><img decoding=\"async\" src=\"https:\/\/www.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-Flattener-Flat73A-voor-ZenithStar-73.jpg\" alt=\"William Optics Flat73A Flattener for ZenithStar 73\" 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-Flattener-Flat73A-voor-ZenithStar-73-4.jpg\" alt=\"William Optics Flat73A Flattener for ZenithStar 73\" 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\">On the train<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">The camera side is M48; with the William Optics M48 adapter for your bayonet, the sensor is directly at the correct distance. You screw M48 filters directly onto the flattener.<\/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\">Connect your camera using the M48 adapter or 48 mm T-ring for your cameramerk.<\/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 ZenithStar 73 owners who photograph<\/li><li>\u2717 ZenithStar 61 owners: the Flat61R is designed for you<\/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 ZenithStar 73<\/td><\/tr><tr><td><strong>Telescope silk<\/strong><\/td><td>M63<\/td><\/tr><tr><td><strong>Camera side<\/strong><\/td><td>M48, with filter thread<\/td><\/tr><tr><td><strong>Backfocus<\/strong><\/td><td>Adjustable, with scale markings<\/td><\/tr><tr><td><strong>Included<\/strong><\/td><td>Gold-colored protective cap<\/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 Flat73A flattener for ZenithStar 73: M63 telescope side, M48 camera side, adjustable back focus with scale and direct M48 filter thread.<\/p>","protected":false},"featured_media":97659,"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-34300","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":[],"acf":[],"jetpack_sharing_enabled":true,"jetpack-related-posts":[{"id":33881,"url":"https:\/\/www.telescoop.nl\/en\/william-optics-zenithstar-73-430-apo-gold-ota\/","url_meta":{"origin":34300,"position":0},"title":"William Optics ZenithStar 73\/430 APO Gold OTA","author":"","date":"15-11-2025","format":false,"excerpt":"William Optics ZenithStar 73 Gold: FPL-53 Apochromatic 73\/430 f\/5.9 for Mobile Astrophotography. Supplied with tube rings, Vixen dovetail, handle with prism clamp, Bahtinov mask, and carrying case.","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-AP-73-430-73-Apochromatische-refractor-Super-ZenithStar-Gold-OTA-2.jpg?resize=350%2C200&ssl=1","width":350,"height":200},"classes":[]},{"id":34224,"url":"https:\/\/www.telescoop.nl\/en\/william-optics-flat-gt-flattener-gran-turismo-refractor-2-inch\/","url_meta":{"origin":34300,"position":1},"title":"William Optics Flat GT Flattener for GranTurismo Refractor","author":"","date":"17-11-2025","format":false,"excerpt":"William Optics Flat GT flattener for the GranTurismo 71 and 81: M63 telescope side, M48 camera side with filter thread, full-frame correction, and only 22 mm long.","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-Flat-GT-1.jpg?resize=350%2C200&ssl=1","width":350,"height":200},"classes":[]},{"id":34298,"url":"https:\/\/www.telescoop.nl\/en\/william-optics-flat68iii-flattener\/","url_meta":{"origin":34300,"position":2},"title":"William Optics Flat68III Flattener","author":"","date":"17-11-2025","format":false,"excerpt":"William Optics Flat68III flattener: Ohara glass with full FMC coating, adjustable back focus with locking ring, M92 telescope side, T2 camera side, and integrated M48 filter thread.","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-Flat68III-Flattener-1.jpg?resize=350%2C200&ssl=1","width":350,"height":200},"classes":[]},{"id":34085,"url":"https:\/\/www.telescoop.nl\/en\/william-optics-flat61r-61-field-flattener-zenithstar\/","url_meta":{"origin":34300,"position":3},"title":"William Optics Flat61R 61 Field Flattener for ZenithStar","author":"Info telescoop","date":"16-11-2025","format":false,"excerpt":"William Optics Flat61R flattener for the ZenithStar 61 and GuideStar 61: adjustable M54 connection, M48 camera side, and integrated M48 filter thread. Round stars all the way to the corners.","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-Flat61R-61-Beeldveldegalisator-voor-ZenithStar-1.jpg?resize=350%2C200&ssl=1","width":350,"height":200},"classes":[]},{"id":34167,"url":"https:\/\/www.telescoop.nl\/en\/william-optics-m63-rotator-adapters-voor-focusers\/","url_meta":{"origin":34300,"position":4},"title":"William Optics M63 Rotator Adapters for Focusers","author":"","date":"17-11-2025","format":false,"excerpt":"William Optics M63 rotator for 2.5-inch focusers: rotate your camera to the desired framing without unthreading the train or losing focus. For Z73, Z103, Z126, GT71, GT81 and more.","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2025\/11\/William-Optics-Rotator-Adapters-voor-M63-focusers.jpg?resize=350%2C200&ssl=1","width":350,"height":200},"classes":[]},{"id":34116,"url":"https:\/\/www.telescoop.nl\/en\/william-optics-71-73-zenithstar-transporttas\/","url_meta":{"origin":34300,"position":5},"title":"William Optics 71 &amp; 73 ZenithStar Transport Bag","author":"","date":"17-11-2025","format":false,"excerpt":"William Optics transport bag for the ZenithStar 71 or 73: sturdy nylon with zipper, made for the original foam insert of your telescope.","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]}],"_links":{"self":[{"href":"https:\/\/www.telescoop.nl\/en\/wp-json\/wp\/v2\/product\/34300","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.telescoop.nl\/en\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/www.telescoop.nl\/en\/wp-json\/wp\/v2\/types\/product"}],"replies":[{"embeddable":true,"href":"https:\/\/www.telescoop.nl\/en\/wp-json\/wp\/v2\/comments?post=34300"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.telescoop.nl\/en\/wp-json\/wp\/v2\/media\/97659"}],"wp:attachment":[{"href":"https:\/\/www.telescoop.nl\/en\/wp-json\/wp\/v2\/media?parent=34300"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/www.telescoop.nl\/en\/wp-json\/wp\/v2\/product_brand?post=34300"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/www.telescoop.nl\/en\/wp-json\/wp\/v2\/product_cat?post=34300"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/www.telescoop.nl\/en\/wp-json\/wp\/v2\/product_tag?post=34300"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}