{"product_id":"bresser-linza-barlou-bresser-3x-125-achromatic-12157","title":"Bresser 3x 1.25\" Achromatic Barlow Lens (12157)","description":"\u003cp\u003e\u003cstrong\u003eThe BRESSER 3x Achromatic Barlow\u003c\/strong\u003e is an optical accessory with a standard mounting diameter of 1.25\" (31.7 mm), which increases the effective focal length of the telescope and the magnification of the eyepiece by a factor of three. The achromatic design corrects chromatic aberrations, providing a sharp image with good contrast across the entire field. The Barlow is installed between the telescope and the eyepiece and allows for high magnification while maintaining the convenient large eyepiece and comfortable pupil distance of the long-focus eyepiece. This is the golden mean among Barlows: it provides more magnification than 2x, but, unlike 5x, remains within the useful range on most telescopes when selecting the appropriate eyepiece. Due to the tripling of the magnification, one Barlow actually adds several more high magnification steps to the set. Combining a long-focus eyepiece with this Barlow gives a sharper and more comfortable image than using a very short eyepiece with a narrow pupil distance. Accessory Equally suitable for visual observations of the Moon and planets and for astrophotography, it is one of the most popular and versatile ways to increase the magnification of an existing telescope.\u003c\/p\u003e\u003cp\u003e \u003cstrong\u003eHow it works (tripling effect on your glasses)\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e A 3x Barlow lens triples the magnification of any eyepiece — or, what is the same, reduces its effective focal length by a factor of three:\u003c\/p\u003e\u003cp\u003e 40 mm eyepiece → works as 13.3 mm\u003cbr \/\u003e 20 mm eyepiece → works as 6.7 mm\u003cbr \/\u003e 15 mm eyepiece → works like 5 mm\u003cbr \/\u003e 10 mm eyepiece → works as 3.3 mm\u003c\/p\u003e\u003cp\u003e Total magnification = telescope focal length ÷ eyepiece effective focal length. Guidelines for our telescopes (keep the result within the useful magnification of the telescope):\u003c\/p\u003e\u003cp\u003e 70\/900 Sirius (ceiling ~140x): with a 20 mm eyepiece — 135x (almost ceiling).\u003cbr \/\u003e 90\/900 Taurus (ceiling ~180x): from 20 mm - 135x, from 15 mm - 180x.\u003cbr \/\u003e 8\" NT-203\/1000 (ceiling ~400x): from 15 mm - 200x, from 10 mm - 300x.\u003cbr \/\u003e 12\" Dobson (ceiling ~610x): from 15 mm - 305x, from 10 mm - 457x.\u003c\/p\u003e\u003cp\u003e \u003cstrong\u003eDesign features\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\u003cli\u003e \u003cstrong\u003eTriple magnification (3x)\u003c\/strong\u003e — the lens triples the magnification of any eyepiece. This allows you to get high magnifications for detailed viewing of planets and the Moon from existing eyepieces. The effective focal length of the telescope is also tripled. The user gets several additional magnification steps without having to buy new short eyepieces.\u003c\/li\u003e\u003cli\u003e \u003cstrong\u003eAchromatic optical scheme\u003c\/strong\u003e - the lenses are designed to bring the primary colors of the spectrum into a single focus. This significantly reduces the color fringing that would otherwise increase at high magnification. The image remains clear and contrasty across the field. The user receives noticeably better quality than from the simplest non-achromatic Barlows.\u003c\/li\u003e\u003cli\u003e \u003cstrong\u003eUniversal magnification for the entire model range\u003c\/strong\u003e - unlike 5x, 3x remains within the useful magnification range on most telescopes when choosing the appropriate eyepiece. This makes 3x the most balanced choice - from beginner refractors to 8-inch reflectors. The Barlow is equally suitable for planets, the Moon and small bright objects. The user gets a working high magnification on almost any instrument.\u003c\/li\u003e\u003cli\u003e \u003cstrong\u003eThe comfort of a long-focus eyepiece at high magnification\u003c\/strong\u003e — Barlow allows you to get high magnification using an eyepiece with a large, comfortable eyepiece. This achieves high detail without the discomfort of short glasses with tiny pupil displacement. This is especially valuable for those who observe with glasses. The user gets high magnification with viewing comfort.\u003c\/li\u003e\u003cli\u003e \u003cstrong\u003eDual purpose: visual and photo\u003c\/strong\u003e - Barlow is equally suitable for eye observations and astrophotography. In visual, it increases the magnification on the Moon and planets, in photo - the scale of the object on the matrix. Achromatic optics maintain quality in both modes. The user...","brand":"Bresser","offers":[{"title":"Default Title","offer_id":47661833158833,"sku":"932393_sv","price":2960.35,"currency_code":"UAH","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0538\/8517\/3937\/files\/1782895578841_df9u17_77163045250303__00920c1968.jpg?v=1782895581","url":"https:\/\/usefulrare.com\/products\/bresser-3x-125-achromatic-barlow-lens-12157","provider":"Dostavka","version":"1.0","type":"link"}