{"id":87,"date":"2022-04-28T12:39:17","date_gmt":"2022-04-28T11:39:17","guid":{"rendered":"http:\/\/mollet-cornelis.be\/wordpress2\/?p=87"},"modified":"2022-05-14T22:44:10","modified_gmt":"2022-05-14T21:44:10","slug":"50cm-newtonian","status":"publish","type":"post","link":"http:\/\/mollet-cornelis.be\/wordpress2\/2022\/04\/28\/50cm-newtonian\/","title":{"rendered":"50cm Newtonian"},"content":{"rendered":"\n

50cm Newtonian on very heavy mount<\/strong><\/h2>\n\n\n\n

Update 2022-05-14:<\/p>\n\n\n\n

Today, we unmounted the big telescope: first the primary mirror, then the secondary and finally we took the “skeleton” (the truss-tube) of the mount.<\/p>\n\n\n\n

And we were in for a big surprise: once we cleaned bit mirrors (very very delicately, first removing all the dust under running water – and then cleaning it with an oh-so-soft soapy water) both looked almost perfectly! No oxidation, nor any other deterioration. They are almost as good as new!<\/p>\n\n\n\n

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After cleaning! Not the slightest trace of oxidation\u2026<\/figcaption><\/figure>\n\n\n\n
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Before the cleaning: even in a closed telescope tube one still gets a lot of dust…<\/figcaption><\/figure>\n\n\n\n
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After the cleaning…<\/figcaption><\/figure>\n\n\n\n
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The truss-tube system (+ the light-weight tube to block stray light) probably weights around 50 kg (not easy to weight such a structure).<\/figcaption><\/figure>\n\n\n\n
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The mirror itself weights almost 27 kg. To that, one should add the mirror cell – the secondary mirror and its spider, and of course the focuser. So all in all, this telescope comes close to 90kg…<\/figcaption><\/figure>\n\n\n\n
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The primary mirror cell, with three ventilators attached to the bars of the “whiffle tree” system. Notice the black triangle – the other 5 are still glued to the underside of the mirror – together with those 3 bars they make up the “whiffle tree”<\/figcaption><\/figure>\n\n\n\n
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One of the 3 bars of the “whiffle tree”.<\/figcaption><\/figure>\n\n\n\n
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The gigantic secondary mirror, with one of the 4 vanes making up the spider.<\/figcaption><\/figure>\n\n\n\n
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Only the tiniest hint of oxidation right at the lower border (on top on this image)<\/figcaption><\/figure>\n\n\n\n
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Underneath the primary mirror: sensors controlling the 3 fans…<\/figcaption><\/figure>\n\n\n\n
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Declination motor block: belt-transmission<\/figcaption><\/figure>\n\n\n\n
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The sheer size of this mount (Knopf MK100S)! The counterweight bar has a diameter of 50mm, and according to the manufacturer it can carry 150 kg of photographic gear).<\/figcaption><\/figure>\n\n\n\n
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Heidenhahn encoders!<\/figcaption><\/figure>\n\n\n\n
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The corrector (Philipp Keller, ASA) reducing the focal ratio to f\/3.3<\/figcaption><\/figure>\n\n\n\n
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The Keller-corrector, here seen next to the huge Apogee-camera for size-comparison.<\/figcaption><\/figure>\n\n\n\n
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50cm Newtonian on very heavy mount Update 2022-05-14: Today, we unmounted the big telescope: first the primary mirror, then the secondary and finally we took the “skeleton” (the truss-tube) of the mount. And we were in for a big surprise: once we cleaned bit mirrors (very very delicately, first removing all the dust under running […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-87","post","type-post","status-publish","format-standard","hentry","category-uncategorised"],"_links":{"self":[{"href":"http:\/\/mollet-cornelis.be\/wordpress2\/wp-json\/wp\/v2\/posts\/87","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/mollet-cornelis.be\/wordpress2\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/mollet-cornelis.be\/wordpress2\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/mollet-cornelis.be\/wordpress2\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/mollet-cornelis.be\/wordpress2\/wp-json\/wp\/v2\/comments?post=87"}],"version-history":[{"count":9,"href":"http:\/\/mollet-cornelis.be\/wordpress2\/wp-json\/wp\/v2\/posts\/87\/revisions"}],"predecessor-version":[{"id":308,"href":"http:\/\/mollet-cornelis.be\/wordpress2\/wp-json\/wp\/v2\/posts\/87\/revisions\/308"}],"wp:attachment":[{"href":"http:\/\/mollet-cornelis.be\/wordpress2\/wp-json\/wp\/v2\/media?parent=87"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/mollet-cornelis.be\/wordpress2\/wp-json\/wp\/v2\/categories?post=87"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/mollet-cornelis.be\/wordpress2\/wp-json\/wp\/v2\/tags?post=87"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}