{"id":33911,"date":"2025-11-15T14:24:36","date_gmt":"2025-11-15T13:24:36","guid":{"rendered":"https:\/\/www.telescoop.nl\/?post_type=product&p=33911"},"modified":"2026-05-18T16:10:36","modified_gmt":"2026-05-18T14:10:36","slug":"william-optics-pleiades-181-998-apo-septuplet-astrograph-ota","status":"publish","type":"product","link":"https:\/\/www.telescoop.nl\/en\/william-optics-pleiades-181-998-apo-septuplet-astrograph-ota\/","title":{"rendered":"William Optics Pleiades 181\/998 APO Septuplet Astrograph OTA"},"content":{"rendered":"

William Optics 181 AP 181\/998 - Powerful deep sky astrograph<\/strong><\/h3>\n\n\n\n

The William Optics 181 AP 181\/998<\/strong> is a top-of-the-line apochromatic refractor built specifically for astrophotography. With the 7-element quadruplet lens and FPL-53 glass, you get bright, sharp images. Full-frame cameras are fully utilized, making stars, nebulae and galaxies look impressive.<\/p>\n\n\n\n

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\"William<\/figure>\n<\/figure>\n\n\n\n

Fast and accurate photography<\/strong><\/h3>\n\n\n\n

With a fast f\/5.5 focal ratio, you can use shorter exposure times. That means less motion blur and faster results. Ideal for deep sky images, but also suitable for Moon and planets.<\/p>\n\n\n\n

Solid rack & pinion focuser<\/strong><\/h3>\n\n\n\n

The 3.7\u2033 R&P focuser lets you focus precisely. Movement is smooth and the ring clamp keeps your accessories stable. Fine adjustment 1:10 helps with precise focus, and everything is rotatable for maximum flexibility. Compatible with electronic focusing such as ZWO EAF.<\/p>\n\n\n\n

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\"William<\/figure>\n<\/figure>\n\n\n\n

Compact and robust design<\/strong><\/h3>\n\n\n\n

Despite its 181 mm aperture, the Pleiades 181 is surprisingly portable. The handle makes transport easy. The telescope supports Losmandy prism beams and can carry William Optics viewfinders or tracking scopes. The included transport bag protects your telescope on the road.<\/p>\n\n\n\n

Complete for astrophotography<\/strong><\/h3>\n\n\n\n

The Pleiades 181 comes with Bahtinov focusing mask and adapters for CCD and DSLR cameras: M48, M54 and M68. It supports Canon, Nikon, Sony, Pentax, Fuji and Micro Four Thirds with optional T-adapters. Everything you need for serious astro shooting.<\/p>\n\n\n\n

Specifications<\/strong><\/h3>\n\n\n\n

Optics<\/strong><\/h4>\n\n\n\n
Feature<\/th>Description<\/th><\/tr><\/thead>
Type<\/td>Refractor<\/td><\/tr>
Design<\/td>Apochromat<\/td><\/tr>
Lens Design<\/td>Quadruplet<\/td><\/tr>
Aperture (mm)<\/td>181<\/td><\/tr>
Focal length (mm)<\/td>998<\/td><\/tr>
Aperture ratio (f\/)<\/td>5,5<\/td><\/tr>
Resolution<\/td>0,76\u2033<\/td><\/tr>
Limit value (mag)<\/td>12,3<\/td><\/tr>
Light output<\/td>670\u00d7<\/td><\/tr>
Max. useful magnification<\/td>362\u00d7<\/td><\/tr>
Corrected field of view (mm)<\/td>55<\/td><\/tr>
Tube length (mm)<\/td>1496<\/td><\/tr>
Transport length (mm)<\/td>1231<\/td><\/tr>
Tube weight (kg)<\/td>15<\/td><\/tr>
Coating<\/td>SMC multilayer coating<\/td><\/tr>
Stray light baffles<\/td>Yes<\/td><\/tr>
Glass material<\/td>OHARA FPL-53<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

Focuser<\/strong><\/h4>\n\n\n\n
Feature<\/th>Description<\/th><\/tr><\/thead>
Design<\/td>Rack & pinion (3.7\u2033)<\/td><\/tr>
Ocular connection<\/td>2\u2033<\/td><\/tr>
Ring clamp<\/td>Yes<\/td><\/tr>
Reduction<\/td>1:10 finesse<\/td><\/tr>
Rotatable<\/td>Yes<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

Mount<\/strong><\/h4>\n\n\n\n
Feature<\/th>Description<\/th><\/tr><\/thead>
Design<\/td>OTA<\/td><\/tr>
Type of mount<\/td>Without mount<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

Included accessories<\/strong><\/h4>\n\n\n\n
Section<\/th>Description<\/th><\/tr><\/thead>
Seeker<\/td>Without<\/td><\/tr>
Dew cap<\/td>Yes<\/td><\/tr>
Dovetail<\/td>Losmandy-Style<\/td><\/tr>
Miscellaneous<\/td>Bahtinov focus mask<\/td><\/tr>
Handle<\/td>Yes<\/td><\/tr>
Transport bag<\/td>Yes<\/td><\/tr>
Corrector<\/td>Integrated<\/td><\/tr>
Camera adapter<\/td>M54<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

General<\/strong><\/h4>\n\n\n\n
Feature<\/th>Description<\/th><\/tr><\/thead>
Color<\/td>Belarus<\/td><\/tr>
Observation goals<\/td>Astrophotography, Moon & Planets, Nebulae & galaxies<\/td><\/tr>
Recommended for<\/td>Advanced<\/td><\/tr>
Observatory use<\/td>Yes<\/td><\/tr><\/tbody><\/table><\/figure>","protected":false},"excerpt":{"rendered":"

William Optics 181 AP 181\/998 comes with an integrated 7-element corrector, 3.7\u2033 R&P focuser, Bahtinov mask, transport bag, Losmandy dovetail, handle and M48, M54 and M68 camera adapters. \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0<\/p>","protected":false},"featured_media":97397,"comment_status":"open","ping_status":"closed","template":"","meta":{"_acf_changed":false},"product_brand":[643],"product_cat":[51,3175,567],"product_tag":[],"class_list":["post-33911","product","type-product","status-publish","has-post-thumbnail","product_brand-william-optics","product_cat-telescopen","product_cat-refractor-ota","product_cat-refractor-telescopen","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":105495,"url":"https:\/\/www.telescoop.nl\/en\/levenhuk-new-skyline-pro-16\/","url_meta":{"origin":33911,"position":0},"title":"Levenhuk New Skyline PRO 16\u2033 \u2013 406\/1830 Dobson","author":"Abdullah Ibrar","date":"03-04-2026","format":false,"excerpt":"The Levenhuk New Skyline PRO 16\" \u2013 406\/1830 Dobson comes with 10 mm and 25 mm Pl\u00f6ssl eyepieces, an 8x40 optical finderscope, and a primary mirror cooling system. 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