{"id":113163,"date":"2026-10-09T16:54:09","date_gmt":"2026-10-09T14:54:09","guid":{"rendered":"https:\/\/www.telescoop.nl\/?post_type=product&p=113163"},"modified":"2026-10-13T11:14:23","modified_gmt":"2026-10-13T09:14:23","slug":"e-180n130-legacy-pre-filter-for-h-alpha-solar-warning-daystar","status":"publish","type":"product","link":"https:\/\/www.telescoop.nl\/en\/erf-voorfilter-e-180n130-voor-h-alpha-zonnewaarneming-daystar\/","title":{"rendered":"ERF pre-filter E-180N130 for H-alpha solar monitoring | DayStar"},"content":{"rendered":"

Anyone who wants to view the Sun in H-alpha with a telescope with a large aperture must first control the heat from the sunlight. The DayStar ERF E-180N130 is designed for this purpose; it is the first filter in an H-alpha setup. It sits in front of the aperture and blocks ultraviolet, infrared, and most of the visible light, while the red light around the H-alpha wavelength passes through.<\/p>\n\n\n\n

At the back of the telescope is the actual H-alpha filter. If you prefer not to combine individual parts, our ready-made solar telescopes<\/a> an alternative.<\/p>\n\n\n\n

Choose the ERF based on your telescope: the mount should fit securely on your tube or dovetail ring, without gaps where unfiltered sunlight can pass through. Therefore, first measure the outer diameter. Never look directly at the sun through an ERF. In our guide on solar eclipse warnings<\/a> Read more about safe observation.<\/p>\n\n\n\n

Need a different size, check here the ERF pre-filter E-170N130<\/a>.<\/p>","protected":false},"excerpt":{"rendered":"

Pre-filter in size E-180N130 that keeps heat, UV and infrared out of your telescope when observing the Sun in H-alpha.<\/p>","protected":false},"featured_media":113155,"comment_status":"open","ping_status":"closed","template":"","meta":{"_acf_changed":false},"product_brand":[3282],"product_cat":[56,3178],"product_tag":[],"class_list":["post-113163","product","type-product","status-publish","has-post-thumbnail","product_brand-daystar","product_cat-telescoop-accessoires","product_cat-zonnefilters","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":113157,"url":"https:\/\/www.telescoop.nl\/en\/erf-voorfilter-e-120n80-voor-h-alpha-zonnewaarneming-daystar\/","url_meta":{"origin":113163,"position":0},"title":"ERF-prefilter E-120N80 for H-alpha solar monitoring | DayStar","author":"Info telescoop","date":"09-10-2026","format":false,"excerpt":"DayStar's E-120N80 pre-filter for H-alpha solar observation, which prevents heat, UV and infrared from entering your telescope before it opens.","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\/12827_1.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/12827_1.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/12827_1.jpg?resize=525%2C300&ssl=1 1.5x"},"classes":[]},{"id":113156,"url":"https:\/\/www.telescoop.nl\/en\/erf-voorfilter-e-110n75-voor-h-alpha-zonnewaarneming-daystar\/","url_meta":{"origin":113163,"position":1},"title":"ERF pre-filter E-110N75 for H-alpha solar monitoring | DayStar","author":"Info telescoop","date":"09-10-2026","format":false,"excerpt":"Energy rejection pre-filter E-110N75 from DayStar for opening your telescope, which prevents UV and infrared radiation during H-alpha observations.","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\/12827_1.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/12827_1.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/12827_1.jpg?resize=525%2C300&ssl=1 1.5x"},"classes":[]},{"id":113160,"url":"https:\/\/www.telescoop.nl\/en\/erf-voorfilter-e-140n100-voor-h-alpha-zonnewaarneming-daystar\/","url_meta":{"origin":113163,"position":2},"title":"ERF pre-filter E-140N100 for H-alpha solar monitoring | DayStar","author":"Info telescoop","date":"09-10-2026","format":false,"excerpt":"Size E-140N100 pre-filter for opening your telescope. It limits the heat on your H-alpha filter during observing the Sun.","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\/12827_1.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/12827_1.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/12827_1.jpg?resize=525%2C300&ssl=1 1.5x"},"classes":[]},{"id":113162,"url":"https:\/\/www.telescoop.nl\/en\/erf-voorfilter-e-170n130-voor-h-alpha-zonnewaarneming-daystar\/","url_meta":{"origin":113163,"position":3},"title":"ERF pre-filter E-170N130 for H-alpha solar monitoring | DayStar","author":"Info telescoop","date":"09-10-2026","format":false,"excerpt":"Energy rejection filter in size E-170N130 for the front of your telescope, so that your H-alpha filter has to process less heat.","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\/12827_1.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/12827_1.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/12827_1.jpg?resize=525%2C300&ssl=1 1.5x"},"classes":[]},{"id":113166,"url":"https:\/\/www.telescoop.nl\/en\/erf-voorfilter-e-325f90-voor-h-alpha-zonnewaarneming-daystar\/","url_meta":{"origin":113163,"position":4},"title":"ERF pre-filter E-325F90 for H-alpha solar monitoring | DayStar","author":"Info telescoop","date":"09-10-2026","format":false,"excerpt":"DayStar ERF pre-filter in size E-325F90 for opening your telescope, which keeps heat, UV and infrared out of your H-alpha setup.","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\/12827_1.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/12827_1.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/12827_1.jpg?resize=525%2C300&ssl=1 1.5x"},"classes":[]},{"id":113158,"url":"https:\/\/www.telescoop.nl\/en\/erf-voorfilter-e-120n100-voor-h-alpha-zonnewaarneming-daystar\/","url_meta":{"origin":113163,"position":5},"title":"ERF pre-filter E-120N100 for H-alpha solar monitoring | DayStar","author":"Info telescoop","date":"09-10-2026","format":false,"excerpt":"Energy rejection pre-filter E-120N100 from DayStar that protects your H-alpha filter and telescope from the heat, UV and infrared of the sun.","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\/12827_1.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/12827_1.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/12827_1.jpg?resize=525%2C300&ssl=1 1.5x"},"classes":[]}],"_links":{"self":[{"href":"https:\/\/www.telescoop.nl\/en\/wp-json\/wp\/v2\/product\/113163","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=113163"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.telescoop.nl\/en\/wp-json\/wp\/v2\/media\/113155"}],"wp:attachment":[{"href":"https:\/\/www.telescoop.nl\/en\/wp-json\/wp\/v2\/media?parent=113163"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/www.telescoop.nl\/en\/wp-json\/wp\/v2\/product_brand?post=113163"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/www.telescoop.nl\/en\/wp-json\/wp\/v2\/product_cat?post=113163"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/www.telescoop.nl\/en\/wp-json\/wp\/v2\/product_tag?post=113163"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}