{"id":112914,"date":"2026-10-09T16:52:48","date_gmt":"2026-10-09T14:52:48","guid":{"rendered":"https:\/\/www.telescoop.nl\/?post_type=product&#038;p=112914"},"modified":"2026-10-09T20:32:27","modified_gmt":"2026-10-09T18:32:27","slug":"adjustment-screws-for-the-catch-mirror-of-the-gso-6-inch-classic-cassegrain-bobs-knobs","status":"publish","type":"product","link":"https:\/\/www.telescoop.nl\/en\/afstelschroeven-voor-de-vangspiegel-van-de-gso-6-inch-klassieke-cassegrain-bobs-knobs\/","title":{"rendered":"Adjusting screws for the viewfinder of the GSO 6 inch classic Cassegrain | Bob\u2019s Knobs"},"content":{"rendered":"<p class=\"wp-block-paragraph\">At high magnification on the moon or Jupiter, you can immediately see if your Cassegrain is properly aligned. A classic Cassegrain works with a parabolic primary mirror and a convex secondary mirror, and that secondary mirror must be exactly aligned. These adjustment screws for the GSO Cassegrain 6-inch are knobs from Bob\u2019s Knobs that you turn by hand.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The set is intended for the 6-inch classic Cassegrain from GSO. That is a telescope with a long focal length, and like a Newton it belongs to the <a href=\"https:\/\/www.telescoop.nl\/en\/telescopes\/reflector-telescopes\/\">reflector telescopes<\/a>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Replace the screws one by one and then adjust them to a bright star. If you want to know what to expect on a good night, read our <a href=\"https:\/\/www.telescoop.nl\/en\/jupiter-through-a-telescope\/\">guide about Jupiter<\/a>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">There is one for the 8 inch version. <a href=\"https:\/\/www.telescoop.nl\/en\/adjustment-screws-for-the-catch-mirror-of-the-gso-8-inch-classic-cassegrain-bobs-knobs\/\">Set for the GSO 8 inch Cassegrain<\/a>.<\/p>","protected":false},"excerpt":{"rendered":"<p>Adjustment buttons for the convex viewfinder of the GSO 6 inch classic Cassegrain, by Bob\u2019s Knobs.<\/p>","protected":false},"featured_media":112913,"comment_status":"open","ping_status":"closed","template":"","meta":{"_acf_changed":false},"product_brand":[1559],"product_cat":[56,3091],"product_tag":[],"class_list":["post-112914","product","type-product","status-publish","has-post-thumbnail","product_brand-bobs-knobs","product_cat-telescoop-accessoires","product_cat-telescoop-onderdelen","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":112916,"url":"https:\/\/www.telescoop.nl\/en\/afstelschroeven-voor-de-vangspiegel-van-de-gso-8-inch-klassieke-cassegrain-bobs-knobs\/","url_meta":{"origin":112914,"position":0},"title":"Adjustment screws for the viewfinder of the GSO 8 inch classic Cassegrain | Bob\u2019s Knobs","author":"Info telescoop","date":"09-10-2026","format":false,"excerpt":"Adjustment knobs from Bob's Knobs for the viewfinder of the GSO 8 inch classic Cassegrain. Adjusting by hand.","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\/87511_1.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/87511_1.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/87511_1.jpg?resize=525%2C300&ssl=1 1.5x"},"classes":[]},{"id":30391,"url":"https:\/\/www.telescoop.nl\/en\/bobs-knobs-afstelschroeven-voor-meade-lightbridge-en-gso-dobson-secundaire-spiegel\/","url_meta":{"origin":112914,"position":1},"title":"Bob's Knobs Adjusting Screws for Meade LightBridge and GSO Dobson Secondary Mirror","author":"","date":"08-10-2025","format":false,"excerpt":"Bob's Knobs for Meade LightBridge and GSO Dobsons: adjust the secondary mirror by hand, without an Allen wrench.","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"Bob\u2019s Knobs Afstelschroeven voor Meade LightBridge en GSO Dobson Secundaire Spiegel","src":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2025\/10\/Bobs-Knobs-Kartelschroeven-voor-vangspiegel-van-Meade-Lightbridge-en-GSO.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2025\/10\/Bobs-Knobs-Kartelschroeven-voor-vangspiegel-van-Meade-Lightbridge-en-GSO.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2025\/10\/Bobs-Knobs-Kartelschroeven-voor-vangspiegel-van-Meade-Lightbridge-en-GSO.jpg?resize=525%2C300&ssl=1 1.5x, https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2025\/10\/Bobs-Knobs-Kartelschroeven-voor-vangspiegel-van-Meade-Lightbridge-en-GSO.jpg?resize=700%2C400&ssl=1 2x, https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2025\/10\/Bobs-Knobs-Kartelschroeven-voor-vangspiegel-van-Meade-Lightbridge-en-GSO.jpg?resize=1050%2C600&ssl=1 3x, https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2025\/10\/Bobs-Knobs-Kartelschroeven-voor-vangspiegel-van-Meade-Lightbridge-en-GSO.jpg?resize=1400%2C800&ssl=1 4x"},"classes":[]},{"id":30398,"url":"https:\/\/www.telescoop.nl\/en\/bobs-knobs-afstelschroeven-voor-celestron-sct-11-f-10-metric\/","url_meta":{"origin":112914,"position":2},"title":"Bob's Knobs Adjusting Screws for Celestron SCT 11\u2033 f\/10 Metric","author":"","date":"08-10-2025","format":false,"excerpt":"Bob's Knobs for the Celestron 11-inch f\/10 SCT Metric: stainless steel thumb screws for secure, tool-free secondary mirror collimation.","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"Bob\u2019s Knobs Afstelschroeven voor Celestron SCT 11\" f\/10 Metric","src":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2025\/10\/Bobs-Knobs-SCT-11-f-10-metric.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2025\/10\/Bobs-Knobs-SCT-11-f-10-metric.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2025\/10\/Bobs-Knobs-SCT-11-f-10-metric.jpg?resize=525%2C300&ssl=1 1.5x, https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2025\/10\/Bobs-Knobs-SCT-11-f-10-metric.jpg?resize=700%2C400&ssl=1 2x, https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2025\/10\/Bobs-Knobs-SCT-11-f-10-metric.jpg?resize=1050%2C600&ssl=1 3x, https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2025\/10\/Bobs-Knobs-SCT-11-f-10-metric.jpg?resize=1400%2C800&ssl=1 4x"},"classes":[]},{"id":30394,"url":"https:\/\/www.telescoop.nl\/en\/bobs-knobs-afstelschroeven-voor-celestron-sct-8-post-1980-standard\/","url_meta":{"origin":112914,"position":3},"title":"Bob's Knobs Adjusting screws for Celestron SCT 8\u2033 (post-1980 Standard)","author":"","date":"08-10-2025","format":false,"excerpt":"Bob's Knobs for the Celestron 8-inch SCT (post-1980 Standard): Stainless steel thumbscrews for secure, tool-free collimation of the secondary mirror.","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"Afstelschroeven voor Celestron SCT","src":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2025\/10\/Bobs-Knobs-SCT-8-post-1980-Standard-.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2025\/10\/Bobs-Knobs-SCT-8-post-1980-Standard-.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2025\/10\/Bobs-Knobs-SCT-8-post-1980-Standard-.jpg?resize=525%2C300&ssl=1 1.5x, https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2025\/10\/Bobs-Knobs-SCT-8-post-1980-Standard-.jpg?resize=700%2C400&ssl=1 2x, https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2025\/10\/Bobs-Knobs-SCT-8-post-1980-Standard-.jpg?resize=1050%2C600&ssl=1 3x, https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2025\/10\/Bobs-Knobs-SCT-8-post-1980-Standard-.jpg?resize=1400%2C800&ssl=1 4x"},"classes":[]},{"id":30397,"url":"https:\/\/www.telescoop.nl\/en\/bobs-knobs-afstelschroeven-voor-celestron-sct-9-25-f-10-standard\/","url_meta":{"origin":112914,"position":4},"title":"Bob's Knobs Adjusting Screws for Celestron SCT 9.25\u2033 f\/10 Standard","author":"","date":"08-10-2025","format":false,"excerpt":"Bob\u2019s Knobs for the Celestron SCT 9.25 inch f\/10 Standard: Stainless steel thumb screws for secure, tool-free secondary mirror collimation.","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"Afstelschroeven voor Celestron SCT","src":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2025\/10\/Bobs-Knobs-SCT-8-post-1980-Standard-.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2025\/10\/Bobs-Knobs-SCT-8-post-1980-Standard-.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2025\/10\/Bobs-Knobs-SCT-8-post-1980-Standard-.jpg?resize=525%2C300&ssl=1 1.5x, https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2025\/10\/Bobs-Knobs-SCT-8-post-1980-Standard-.jpg?resize=700%2C400&ssl=1 2x, https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2025\/10\/Bobs-Knobs-SCT-8-post-1980-Standard-.jpg?resize=1050%2C600&ssl=1 3x, https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2025\/10\/Bobs-Knobs-SCT-8-post-1980-Standard-.jpg?resize=1400%2C800&ssl=1 4x"},"classes":[]},{"id":112912,"url":"https:\/\/www.telescoop.nl\/en\/afstelschroeven-voor-de-vangspiegel-van-een-5-inch-sct-f-6-bobs-knobs\/","url_meta":{"origin":112914,"position":5},"title":"Adjusting screws for the viewfinder of a 5 inch SCT f\/6 | Bob\u2019s Knobs","author":"Info telescoop","date":"09-10-2026","format":false,"excerpt":"Adjustment knobs from Bob's Knobs for the secondary mirror of a 5 inch Schmidt-Cassegrain with f\/6.","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\/87171_1.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/87171_1.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/87171_1.jpg?resize=525%2C300&ssl=1 1.5x"},"classes":[]}],"_links":{"self":[{"href":"https:\/\/www.telescoop.nl\/en\/wp-json\/wp\/v2\/product\/112914","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=112914"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.telescoop.nl\/en\/wp-json\/wp\/v2\/media\/112913"}],"wp:attachment":[{"href":"https:\/\/www.telescoop.nl\/en\/wp-json\/wp\/v2\/media?parent=112914"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/www.telescoop.nl\/en\/wp-json\/wp\/v2\/product_brand?post=112914"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/www.telescoop.nl\/en\/wp-json\/wp\/v2\/product_cat?post=112914"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/www.telescoop.nl\/en\/wp-json\/wp\/v2\/product_tag?post=112914"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}