{"id":34058,"date":"2025-11-16T15:12:12","date_gmt":"2025-11-16T14:12:12","guid":{"rendered":"https:\/\/www.telescoop.nl\/?post_type=product&p=34058"},"modified":"2026-03-17T14:44:53","modified_gmt":"2026-03-17T13:44:53","slug":"william-optics-61-guidescope-guide-star-apo-blue","status":"publish","type":"product","link":"https:\/\/staging.telescoop.nl\/en\/william-optics-61-guidescope-guide-star-apo-blue\/","title":{"rendered":"William Optics 61 Guidescope Guide Star Apo Blue"},"content":{"rendered":"

Sharp stars for easy tracking<\/strong><\/h3>\n\n\n\n

The William Optics 61 is more than an ordinary viewfinder. The FPL-53 objective ensures sharp constellations. This allows you to accurately track your main telescope without blurring stars. The GS61 works perfectly with refractors from 700 to 1200 mm focal length.<\/p>\n\n\n\n

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

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

With the optional Flat61 flattener, you can also use the GS61 for astrophotography. Ideal for small cameras. This allows you to take clear, sharp images without the hassle.<\/p>\n\n\n\n

Easy focusing<\/strong><\/h3>\n\n\n\n

Helicoidal focusing is through the dew cap. Loosen the ribbed counter ring, slide the hood to focus, and tighten. The retractable rear end gives additional flexibility. So you'll always find the perfect focus quickly.<\/p>\n\n\n\n

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

Solid and practical construction<\/strong><\/h3>\n\n\n\n

The GS61 is aluminum, lightweight (1.44 kg) and 340 mm long. The guidescope has a dovetail for easy mounting and comes with a transport bag. Everything is designed for stability and ease of use.<\/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>
Lens diameter (mm)<\/td>61<\/td><\/tr>
Focal length (mm)<\/td>360<\/td><\/tr>
Aperture ratio (f\/)<\/td>5,9<\/td><\/tr>
Optics coating<\/td>Multiple<\/td><\/tr>
Resolution<\/td>2,3\u2033<\/td><\/tr>
Limit value (mag)<\/td>10,3<\/td><\/tr>
Light output<\/td>50<\/td><\/tr>
Max. useful magnification<\/td>100\u00d7<\/td><\/tr>
Type<\/td>Refractor<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

Focuser<\/strong><\/h4>\n\n\n\n
Feature<\/th>Description<\/th><\/tr><\/thead>
Connection (camera side)<\/td>M54<\/td><\/tr>
Ocular connection<\/td>2\u2033<\/td><\/tr>
Fine control<\/td>Yes<\/td><\/tr>
Ring clamp<\/td>Yes<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

Mounting & accessories<\/strong><\/h4>\n\n\n\n
Feature<\/th>Description<\/th><\/tr><\/thead>
Dovetail<\/td>Yes<\/td><\/tr>
Transport bag<\/td>Yes<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

General<\/strong><\/h4>\n\n\n\n
Feature<\/th>Description<\/th><\/tr><\/thead>
Type<\/td>Guiding<\/td><\/tr>
Design<\/td>Guidescope<\/td><\/tr>
Exterior material<\/td>Aluminum<\/td><\/tr>
Weight (g)<\/td>1440<\/td><\/tr>
Length (mm)<\/td>340<\/td><\/tr>
Color<\/td>Blue<\/td><\/tr>
Application<\/td>Astrophotography (Guidescope)<\/td><\/tr><\/tbody><\/table><\/figure>","protected":false},"excerpt":{"rendered":"

William Optics 61 comes with FPL-53 glass for sharp stars, a helicoidal focus, Vixen-style dovetail and a transport bag. \u00a0<\/p>","protected":false},"featured_media":97489,"comment_status":"open","ping_status":"closed","template":"","meta":{"_acf_changed":false},"product_brand":[643],"product_cat":[469,3064,3104,56],"product_tag":[],"class_list":["post-34058","product","type-product","status-publish","has-post-thumbnail","product_brand-william-optics","product_cat-astro-fotografie","product_cat-guidescopes","product_cat-overige-astrofotografie-accessoires","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":[],"acf":[],"jetpack_sharing_enabled":true,"jetpack-related-posts":[{"id":34051,"url":"https:\/\/staging.telescoop.nl\/en\/william-optics-61-guidescope-guide-star-apo-goud\/","url_meta":{"origin":34058,"position":0},"title":"William 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