{"id":34143,"date":"2025-11-17T13:22:14","date_gmt":"2025-11-17T12:22:14","guid":{"rendered":"https:\/\/www.telescoop.nl\/?post_type=product&#038;p=34143"},"modified":"2026-10-13T11:15:19","modified_gmt":"2026-10-13T09:15:19","slug":"william-optics-40mm-2-swan-eyepiece","status":"publish","type":"product","link":"https:\/\/www.telescoop.nl\/en\/william-optics-40mm-2-swan-oculair\/","title":{"rendered":"William Optics 40mm 2\u2033 SWAN Eyepiece"},"content":{"rendered":"<h2 class=\"wp-block-heading has-text-align-center\"><strong>William Optics 40mm 2\u2033 SWAN Eyepiece: a window to space<\/strong><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The William Optics SWAN 40 mm is a 2-inch wide-field eyepiece with an apparent field of view of 72 degrees. The combination of long focal length and wide field provides the largest possible patch of sky in a single view: extended nebulae, star fields, and the Milky Way at their finest.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The five-element design is multi-coated and the lens edges are blackened to prevent stray light. With 28 mm of eye relief, viewing is comfortable, even with glasses, and the fold-down eyecup can be adjusted to your preferred viewing position. The filter thread accepts 2-inch filters directly.<\/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-40mm-2-SWAN-Oculair.jpg\" alt=\"William Optics SWAN 40 mm 2 inch eyepiece\" title=\"\"><\/figure><\/figure>\n\n\n\n<h4 class=\"wp-block-heading\">Which telescopes<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">The eyepiece requires a 2-inch focuser or diagonal. On telescopes with a slow f-ratio, the field performs at its tightest; on very fast optics, edge stars become softer, which is typical for this price range.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Featured accessories<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Combine the eyepiece with the Dura Bright 2-inch diagonal for the complete visual overview package.<\/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 Deep-sky observers looking for maximum field of view<\/li><li>\u2713 Glasses wearers, thanks to 28 mm eye relief<\/li><li>\u2717 Owners of 1.25-inch connections only<\/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>Focal length<\/strong><\/td><td>40 mm<\/td><\/tr><tr><td><strong>Apparent field of view<\/strong><\/td><td>72 degrees<\/td><\/tr><tr><td><strong>Optics<\/strong><\/td><td>5 lenses, multi-coated, blackened edges<\/td><\/tr><tr><td><strong>Eye relief<\/strong><\/td><td>28 mm<\/td><\/tr><tr><td><strong>Mount<\/strong><\/td><td>2 inch, with filter thread<\/td><\/tr><tr><td><strong>Eyecup<\/strong><\/td><td>Foldable<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">You can find more accessories for this brand at the <a href=\"\/en\/brands\/william-optics\/\">William Optics brand page<\/a>.<\/p>","protected":false},"excerpt":{"rendered":"<p>William Optics SWAN 40 mm 2-inch eyepiece: 72-degree apparent field of view, 5 lenses, 28 mm eye relief, fully multicoated, and filter thread. Maximum field of view for deep-sky.<\/p>","protected":false},"featured_media":97573,"comment_status":"open","ping_status":"closed","template":"","meta":{"_acf_changed":false},"product_brand":[643],"product_cat":[3131,56],"product_tag":[],"class_list":["post-34143","product","type-product","status-publish","has-post-thumbnail","product_brand-william-optics","product_cat-groothoek-oculairen-wide-field","product_cat-telescoop-accessoires","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":[34220],"acf":[],"jetpack_sharing_enabled":true,"jetpack-related-posts":[{"id":34220,"url":"https:\/\/www.telescoop.nl\/en\/william-optics-90-2-diagonaal-spiegel-dura-bright\/","url_meta":{"origin":34143,"position":0},"title":"William Optics 90\u00b0 2\u2033 Diagonal Mirror Dura Bright","author":"","date":"17-11-2025","format":false,"excerpt":"William Optics Dura Bright 90-degree 2-inch diagonal mirror: 99% dielectric coating, 12 mm mirror at 1\/12 lambda, carbon housing, compression ring, filter thread, and 1.25-inch adapter.","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-90%C2%B0-2-Diagonaal-Spiegel-Dura-Bright-2.jpg?resize=350%2C200&ssl=1","width":350,"height":200},"classes":[]},{"id":34147,"url":"https:\/\/www.telescoop.nl\/en\/william-optics-400mm-losmandy-swan-series-2\/","url_meta":{"origin":34143,"position":1},"title":"William Optics 400mm Losmandy Swan Series","author":"","date":"17-11-2025","format":false,"excerpt":"William Optics 400 mm Losmandy dovetail from the Swan series (gold): wide, rigid profile for heavy tubes and complete imaging 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Shows with three light spikes when a star is exactly sharp.","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/77285_1.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/77285_1.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/77285_1.jpg?resize=525%2C300&ssl=1 1.5x"},"classes":[]}],"_links":{"self":[{"href":"https:\/\/www.telescoop.nl\/en\/wp-json\/wp\/v2\/product\/34143","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=34143"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.telescoop.nl\/en\/wp-json\/wp\/v2\/media\/97573"}],"wp:attachment":[{"href":"https:\/\/www.telescoop.nl\/en\/wp-json\/wp\/v2\/media?parent=34143"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/www.telescoop.nl\/en\/wp-json\/wp\/v2\/product_brand?post=34143"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/www.telescoop.nl\/en\/wp-json\/wp\/v2\/product_cat?post=34143"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/www.telescoop.nl\/en\/wp-json\/wp\/v2\/product_tag?post=34143"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}