{"id":16299,"date":"2026-08-04T19:42:02","date_gmt":"2026-08-04T17:42:02","guid":{"rendered":"https:\/\/deep-space-astronomy.ch\/?post_type=product&p=16299"},"modified":"2026-09-24T11:05:33","modified_gmt":"2026-09-24T09:05:33","slug":"daystar-ulf-50-filtre-solaire-universel-pliable-50-mm","status":"publish","type":"product","link":"https:\/\/deep-space-astronomy.ch\/en\/product\/daystar-ulf-50-filtre-solaire-universel-pliable-50-mm\/","title":{"rendered":"DayStar ULF-50 \u2013 50 mm Foldable Universal Solar Filter"},"content":{"rendered":"
\n

DayStar ULF-50 \u2013 50 mm Foldable Universal Solar Filter<\/h2>\n

The DayStar ULF-50<\/strong> is a versatile, foldable, and affordable solar filter designed to safely observe or photograph the Sun using a camera, a small pair of binoculars, a small telescope, or certain compatible optical instruments.<\/p>\n

Its opening of 50 mm<\/strong> Suitable for instruments with an outer diameter between 50 and 69 mm<\/strong>. In particular, it is compatible with most lenses that come with digital SLR cameras, as well as with lenses that are permanently attached to certain cameras.<\/p>\n

For lenses with an outer diameter at the lower end of this range, the tabs should be folded inward to ensure a better fit around the lens.<\/p>\n

Observing and Photographing the Sun<\/h3>\n

Once properly assembled and positioned in front of the lens, the filter allows you to observe or photograph the Sun with a tint orange, sharp, and high-contrast<\/strong>. It also makes it possible to distinguish large sunspots when they are present.<\/p>\n

In particular, this filter can be used to photograph solar eclipses, clouds passing in front of the solar disk, and changes in large sunspot regions.<\/p>\n

Start with the equipment you already have<\/h3>\n

Lightweight and economical, the ULF-50 allows you to add white-light solar observation to a compatible instrument. You can track large sunspots from one day to the next or take a series of photographs of the solar disk. Measure the outer diameter of your equipment and fully assemble the filter before use.<\/p>\n

Want to learn more about protuberances, too? The Solar Scout SS60DS H-alpha Telescope<\/a> opens up another option in the DayStar line. An ULF filter is not a substitute for an H-alpha system or its energy-rejection filter. For a school activity or a club event, Contact Deep Space Astronomy<\/a> in order to select the equipment and prepare for supervised use.<\/p>\n

Thousand Oaks Window Film<\/h3>\n

The ULF-50 uses a solar film Thousand Oaks Optical, ND 5 density<\/strong>, from a manufacturer listed by the American Astronomical Society as one of its recognized suppliers of solar filters.<\/p>\n

The film rejects 99.999 % of solar radiation<\/strong> and meets the transmission requirements of the standard ISO 12312-2:2015<\/strong> applicable to filters intended for direct observation of the Sun.<\/p>\n

Regulatory clarification:<\/strong> The ISO 12312-2 certification applies to devices such as sunglasses. The ULF-50 is an integrated filter intended to be mounted in front of an optical instrument. It is not designed to be used as a pair of glasses and must never be held directly in front of the eyes.<\/p>\n

Foldable design<\/h3>\n
    \n
  • Effective opening: 50 mm<\/strong><\/li>\n
  • Compatible outer diameter: 50 to 69 mm<\/strong><\/li>\n
  • Thousand Oaks Optical Window Film: density ND 5<\/strong><\/li>\n
  • Reduction of solar radiation: 99,999\u00a0%<\/strong><\/li>\n
  • Double-layer thick cardboard construction<\/li>\n
  • Black interior surface that minimizes unwanted reflections<\/li>\n
  • Foldable tabs that act as springs around the lens<\/li>\n
  • Filter shipped flat in a Stayflat rigid envelope<\/li>\n
  • Assembly required before use<\/li>\n
  • Made in the United States<\/li>\n
  • Bilingual packaging in English and Spanish<\/li>\n<\/ul>\n

    Compatibility<\/h3>\n

    The ULF-50 is primarily recommended for:<\/p>\n

      \n
    • lenses with an outer diameter between 50 and 69 mm; ;<\/li>\n
    • the lenses that come with many digital SLR camera kits; ;<\/li>\n
    • cameras equipped with a compatible fixed lens; ;<\/li>\n
    • small astronomical binoculars; ;<\/li>\n
    • small telescopes and compatible observation instruments.<\/li>\n<\/ul>\n

      Important information:<\/strong> Measure the actual outer diameter of the lens or tube at
      \non which the filter will be installed. The thread size indicated on a camera lens does not
      \ndoes not always correspond to its outer diameter.<\/p>\n

      Essential Safety Guidelines<\/h3>\n
        \n
      • Never look at the sun without special solar protection.<\/li>\n
      • Never use the filter if it is damaged, torn, punctured, or heavily scratched.<\/li>\n
      • Never use the filter when it is flat, unfolded, or partially assembled.<\/li>\n
      • Assemble the filter completely before placing it in front of the instrument.<\/li>\n
      • Inspect the solar film before each use, preferably in front of a light source other than sunlight.<\/li>\n
      • Make sure the filter completely covers the lens opening.<\/li>\n
      • No part of the solar disk should be visible around the filter.<\/li>\n
      • Make sure the tabs are holding the filter securely in place before pointing the instrument at the Sun.<\/li>\n
      • Check that the filter is secure before tilting the lens or telescope downward.<\/li>\n
      • Never remove the filter while the instrument is pointed at the Sun.<\/li>\n
      • Handle the device with care so as not to accidentally dislodge the filter.<\/li>\n
      • Always supervise children and inexperienced users.<\/li>\n
      • Do not use this product as eclipse glasses or as eye protection held in front of your eyes.<\/li>\n<\/ul>\n

        Reference:<\/strong> ULF-50<\/p>\n<\/section>\n<\/div><\/div>","protected":false},"excerpt":{"rendered":"

        Get started with sunspot observation and photography using the DayStar ULF-50, an affordable, foldable white-light filter. Effective aperture of 50 mm, for an outer diameter of 50 to 69 mm; complete assembly required, including aperture cover and secure mounting.<\/p>","protected":false},"featured_media":16300,"comment_status":"open","ping_status":"closed","template":"","meta":[],"product_brand":[834],"product_cat":[645,642],"product_tag":[],"class_list":["post-16299","product","type-product","status-publish","has-post-thumbnail","product_brand-daystar","product_cat-filtres-solaires","product_cat-materiel-pour-lobservation-solaire","first","outofstock","taxable","shipping-taxable","purchasable","product-type-simple"],"_links":{"self":[{"href":"https:\/\/deep-space-astronomy.ch\/en\/wp-json\/wp\/v2\/product\/16299","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/deep-space-astronomy.ch\/en\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/deep-space-astronomy.ch\/en\/wp-json\/wp\/v2\/types\/product"}],"replies":[{"embeddable":true,"href":"https:\/\/deep-space-astronomy.ch\/en\/wp-json\/wp\/v2\/comments?post=16299"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/deep-space-astronomy.ch\/en\/wp-json\/wp\/v2\/media\/16300"}],"wp:attachment":[{"href":"https:\/\/deep-space-astronomy.ch\/en\/wp-json\/wp\/v2\/media?parent=16299"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/deep-space-astronomy.ch\/en\/wp-json\/wp\/v2\/product_brand?post=16299"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/deep-space-astronomy.ch\/en\/wp-json\/wp\/v2\/product_cat?post=16299"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/deep-space-astronomy.ch\/en\/wp-json\/wp\/v2\/product_tag?post=16299"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}