[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"detail-sidebar-cat-0-en-105":3,"doc-seo-269397-105":59,"doc-detail-269397-en":130},{"code":4,"msg":5,"data":6},0,"success",[7,13,18,23,28,33,38,43,48,51,55],{"id":8,"doc_module":4,"doc_module_name":9,"category_name":10,"show_sort_weight":11,"slug":12},1,"Document","Story & Novel",90,"story-novel",{"id":14,"doc_module":4,"doc_module_name":9,"category_name":15,"show_sort_weight":16,"slug":17},2,"Literature",80,"literature",{"id":19,"doc_module":4,"doc_module_name":9,"category_name":20,"show_sort_weight":21,"slug":22},4,"Exam",70,"exam",{"id":24,"doc_module":4,"doc_module_name":9,"category_name":25,"show_sort_weight":26,"slug":27},5,"Comic",60,"comic",{"id":29,"doc_module":4,"doc_module_name":9,"category_name":30,"show_sort_weight":31,"slug":32},6,"Technology",50,"technology",{"id":34,"doc_module":4,"doc_module_name":9,"category_name":35,"show_sort_weight":36,"slug":37},7,"Healthcare",40,"healthcare",{"id":39,"doc_module":4,"doc_module_name":9,"category_name":40,"show_sort_weight":41,"slug":42},8,"Research & Report",30,"research-report",{"id":44,"doc_module":4,"doc_module_name":9,"category_name":45,"show_sort_weight":46,"slug":47},9,"Religion & Spirituality",20,"religion-spirituality",{"id":46,"doc_module":4,"doc_module_name":9,"category_name":49,"show_sort_weight":46,"slug":50},"World Cup","world-cup",{"id":52,"doc_module":4,"doc_module_name":9,"category_name":53,"show_sort_weight":52,"slug":54},10,"Lifestyle","lifestyle",{"id":56,"doc_module":4,"doc_module_name":9,"category_name":57,"show_sort_weight":24,"slug":58},19,"General","general",{"code":4,"msg":60,"data":61},"ok",{"site_id":62,"language":63,"slug":64,"title":65,"keywords":66,"description":67,"schema_data":68,"social_meta":123,"head_meta":125,"extra_data":127,"updated_unix":129},105,"en","collimation-of-fixed-primary-mirror-reflectors-collimation","Collimation of Fixed-Primary Mirror Reflectors - Collimation","","Collimation describes how to adjust a reflector telescope’s optical elements so they remain aligned and deliver peak performance. It explains why alignment may drift after the telescope is jarred and why regular checks matter. The guide shows how to evaluate collimation by looking into the focuser drawtube, using a quick collimation cap for clearer mirror reflections, and applying step-by-step adjustments to the secondary mirror’s setscrews. It also includes guidance for preparing the telescope and using a star test to confirm symmetry.",{"@graph":69,"@context":122},[70,84,105],{"@type":71,"itemListElement":72},"BreadcrumbList",[73,77,79,82],{"item":74,"name":75,"@type":76,"position":8},"https://docshare.wps.com","Home","ListItem",{"item":78,"name":9,"@type":76,"position":14},"https://docshare.wps.com/document/",{"item":80,"name":30,"@type":76,"position":81},"https://docshare.wps.com/document/technology/",3,{"item":83,"name":65,"@type":76,"position":19},"https://docshare.wps.com/document/collimation-of-fixed-primary-mirror-reflectors-collimation/269397/",{"url":83,"name":65,"@type":85,"image":86,"author":91,"headline":65,"publisher":94,"fileFormat":97,"inLanguage":63,"description":67,"dateModified":98,"datePublished":99,"encodingFormat":97,"isAccessibleForFree":100,"interactionStatistic":101},"DigitalDocument",{"url":87,"@type":88,"width":89,"height":90},"https://docshare.wps.com/thumbnails/collimation-of-fixed-primary-mirror-reflectors-collimation/269397.png","ImageObject",300,407,{"name":92,"@type":93},"Bill Black","Person",{"url":74,"name":95,"@type":96},"DocShare","Organization","application/pdf","2026-10-09","2026-09-15",true,{"@type":102,"interactionType":103,"userInteractionCount":44},"InteractionCounter",{"@type":104},"ViewAction",{"@type":106,"mainEntity":107},"FAQPage",[108,114,118],{"name":109,"@type":110,"acceptedAnswer":111},"What is collimation in a reflector telescope and why is it important?","Question",{"text":112,"@type":113},"Collimation is the process of adjusting a telescope’s optical elements so they are aligned with one another. Accurate alignment ensures peak performance, and it should be checked regularly because the mirrors can shift out of alignment.","Answer",{"name":115,"@type":110,"acceptedAnswer":116},"How do you check whether the telescope is properly collimated?",{"text":117,"@type":113},"Remove the eyepiece and look down the focuser drawtube. The centered reflections of the secondary mirror, the primary mirror, and the secondary mirror (and your eye) should align as described; if any reflection is off-center, follow the collimating procedure.",{"name":119,"@type":110,"acceptedAnswer":120},"What procedure is used to align the secondary mirror?",{"text":121,"@type":113},"Use the correct Allen key (often 2mm or 2.5mm). Loosen one of the three recessed setscrews by no more than 1/4 turn, then lightly tighten the other two to remove slack, repeatedly checking whether the primary mirror reflection becomes centered. Tighten all three setscrews at the end without overtightening.","https://schema.org",{"og:url":83,"og:type":124,"og:title":65,"og:site_name":95,"og:description":67},"article",{"robots":126,"canonical":83},"index,follow",{"doc_id":128,"site_id":62},269397,1789451267,{"code":4,"msg":5,"data":131},{"doc_id":128,"user_id":132,"nickname":92,"user_avatar":133,"doc_module":4,"category_id":29,"category_name":30,"doc_title":65,"doc_description":67,"doc_content":134,"file_id":135,"file_url":136,"file_type":137,"file_size":138,"view_count":44,"is_deleted":4,"is_public":8,"is_downloadable":8,"audit_status":8,"page_count":14,"language":139,"language_code":63,"site_id":62,"html_lang":63,"table_of_contents":140,"faqs":141,"seo_title":142,"seo_description":67,"update_tm":129,"read_time":24},24189269381491,"https://ap-avatar.wpscdn.com/avatar/160000cf11732dd8392?x-image-process=image/resize,m_fixed,w_180,h_180&k=1788146458752108895","Collimation of Fixed‑Primary Mirror Reflectors  \nCollimation  \nCollimation is the process of adjusting the telescope’s optical elements so they are aligned with one another. Your reflector telescope’s optics were aligned at the factory, and should not need much adjustment unless the telescope was jarred while in transit. Accurate mirror alignment is important to ensure the peak performance of your telescope. And since the mirrors can go out of alignment occasionally, it should be checked regularly.  \nCollimation is a relatively easy process and can be done in daylight or darkness. To check collimation, remove the eyepiece and look down the focuser drawtube. You should seethe secondary mirror centered in the drawtube, as well as the reflection of the primary mirror centered in the secondary mirror, and the reflection of the secondary mirror (and your eye) centered in the reflection of the primary mirror, as in Figure 1a. If anything is off-center, proceed with the following collimating procedure.  \nThe Collimation Cap  \nYour Orion reflector telescope comes with a “quick collimation cap,” shown in Figure 2. This is a simple cap that fits on the focuser drawtube like a dust cap, but has a tiny hole in the center and a reflective inner surface. The collimation cap helps center your eye over the focuser drawtube, making it easier to align the optical components. The reflective surface provides a distinct visual reference that is helpful in centering the mirror reflections. Figures 1b and 1c assume that you have the collimation cap in place.  \nPrimary Mirror Center Mark?  \nThe primary mirror of your reflector telescope may or may not have a tiny ring (sticker) marking its center. This “center mark” is helpful in achieving a precise collimation, but it is not needed in telescopes in which the primary mirror was aligned at the factory and fixed in place. If it is there, do not remove it as it does not affect the view through the telescope in any way. If there is no ring on the primary mirror, that’s OK as it is not needed.  \nProviding Exceptional Consumer Optical Products Since 1975  \nCustomer Support: [www.OrionTelescopes.com/contactus](www.OrionTelescopes.com/contactus)[ ](www.OrionTelescopes.com/contactus)Corporate Offices:  \n89 Hangar Way, Watsonville CA 95076-USA  \nCopyright © 2014 Orion Telescopes & Binoculars All Rights Reserved. No part of this product instruction or any of its contents may be reproduced, copied, modified or adapted, without the prior written consent of Orion Telescopes & Binoculars.  \nFigure 1. Collimating the optics. (a) When the mirrors are properly aligned, the view down the focuser drawtube should look like this; (b) With the collimation cap in place, if the optics are out of alignment, the view might look something like this; (c) After adjusting the secondary collimation setscrews, the reflection of the primary mirror should be centered in the secondary mirror as shown.  \nFigure 2. The quick collimation cap, which features a reflective inner surface, helps in centering reflections of the optics in the focuser during the collimation process.  \nWaRning: Never look directly at the Sun with the naked eye or with a telescope – unless you have a proper solar filter installed over the front of the telescope! Otherwise, permanent, irreversible eye damage may result.  \nPreparing the Telescope for Collimation  \nOnce you get the hang of collimating, you will be able to do it quickly even in the dark. For now, it is best to collimate in daylight, preferably in a brightly lit room and aimed at a white wall. It is recommended that the telescope tube be oriented horizontally. This will prevent any parts from the secondary mirror from falling down onto the primary mirror and causing damage if something comes loose while you are making adjustments. Place a small sheet of white paper inside the optical tube directly opposite the focuser (Figure 3). The paper will provide a bright “background” when viewing into the focuser","cbCairN0rWxcuzj8","https://ap.wps.com/l/cbCairN0rWxcuzj8","pdf",492156,"English","# Collimation\n## Checking collimation with the focuser drawtube\n## The collimation cap\n## Primary mirror center mark\n## Preparing the telescope for collimation\n## Aligning the secondary mirror\n## Aligning the primary mirror\n## Star testing the telescope","[{\"question\":\"What is collimation in a reflector telescope and why is it important?\",\"answer\":\"Collimation is the process of adjusting a telescope’s optical elements so they are aligned with one another. Accurate alignment ensures peak performance, and it should be checked regularly because the mirrors can shift out of alignment.\"},{\"question\":\"How do you check whether the telescope is properly collimated?\",\"answer\":\"Remove the eyepiece and look down the focuser drawtube. The centered reflections of the secondary mirror, the primary mirror, and the secondary mirror (and your eye) should align as described; if any reflection is off-center, follow the collimating procedure.\"},{\"question\":\"What procedure is used to align the secondary mirror?\",\"answer\":\"Use the correct Allen key (often 2mm or 2.5mm). Loosen one of the three recessed setscrews by no more than 1/4 turn, then lightly tighten the other two to remove slack, repeatedly checking whether the primary mirror reflection becomes centered. Tighten all three setscrews at the end without overtightening.\"}]","Collimation of Fixed-Primary Mirror Reflectors - Collimation | PDF"]