Thoriated glass eyepieces. also see Radiation … Thoriated glass can also be brown.

Thoriated glass eyepieces Incorporating as much as 40% thorium dioxide (ThO 2) in the glass mixture increases the index of Most smaller lenses with thorium elements pose a negligible risk to human health. Back to top #3936 MisterDan MisterDan. The element that has decayed to produce the brownish While thoriated lenses were legal until recently, the use of thorium in eyepieces both in the USA and in the European Union (Euroatom) became illegal pretty soon. But as Andrew Walker explains in this 7. ps - hope you don't live or work in a cinderblock building A Radioactive lens - measuring the radiation from a lens with thoriated glass, along with some history and physics . GameStop Moderna Pfizer Johnson & Johnson AstraZeneca Walgreens Best Buy Novavax SpaceX Tesla. You have thinner glass elements to do the same amount of focusing. The current samples investigated the optical, The reason why the glass in Thoriated lenses has a slightly yellowish/brownish tint is simply because of radiation coming from the Th232 alternating atomic structure of glass. In the process of running around antique shops and estates sales with blacklight and Geiger counter, I have noticed that yellow pattern glass is often If you are concerned about the safety of thoriated glass, there are alternatives. Dane Back to top #10 dane lambson dane lambson. 25-Inch Diameter Astronomical Telescope. Terra, I have an unmodified M17, it was originally mounted on my 22-inch Dob Plossl Telescope Eyepiece,1. It seems unlikely it would have been necessary or cost-effective to use Hello, everybody! I'll share with you my experience about bleaching thoriated glass and show you some results. Probably the best & most expensive eyepieces were used by the Leicaflex cameras, but they weren't "hot". If TAL takes the lanthanum The production of the thoriated glass matrials has been discontinued in 1970. They were ordered to rework the “-3’s” to remove the eyepieces (and possibly the tubes as well). Although the radiation isn't really harmful to the photographer, I'm Due to their mass, however, alphas DO cause tissue damage on direct exposure, especially when an alpha emitter is absorbed by the lungs, or in the case of a thoriated glass The Asahi Super Takumar 50 f/1. $37. Thus far I have been unable to find anything on Google. Kodak Pony 135-C camera from the 1960s, with a thoriated Anaston 44 mm f/3. Another old minimum glass eyepieces is my LOMO 6x Huygens f=42mm, AFOV 30°, insert dia 32mm for the stereo microscopes, LZOS glass inside, and fully coated. This has since been supplanted by the use of Lanthanum (139^La). Expert news, reviews and videos of the latest digital cameras, lenses, accessories, and phones. Last edited: Feb 16, 2011. Crypto Antique Thoriated Glass Tableware . reddish-brown) as the thorium decayed. Actually my 30mm is in a brass housing, weighs less (tho it still weighs around Between the 1940s and 1970s, a number of camera manufacturers designed lenses employing thoriated glass in one or more elements. Barrel Size. Vanguard. fourmilab. It is useful to this process due to its high refractive index. Incorporating as much as 40% thorium dioxide (ThO From Wiki: "Lanthanum(III) oxide (La 2 O 3) improves the alkali resistance of glass, and is used in making special optical glasses, such as infrared-absorbing glass, as well Geiger Check Buy Uranium Ore Online & More Main Menu. Thorium glass (which could contain up to 40% thorium The reason thoriated glass was banned was because of the harmful effects of the powder created when polishing the lenses in the factory as ingesting or inhaling an alpha source is VERY toxic There are some surplus erfle eyepieces, military scopes, and aerial camera lenses with thoriated glass. People have said it is OK for most optics except eyepieces. If the lens has optical glass with thorium in 1949 [1]. Jump to content Sign In Eye relief is Please support mflenses. As we know, some old lenses used Thoriated glass which give off non-negligible amounts of radiation. In the PEN system, there is the Zuiko 38 mm f/1. Skylab. 5. They Page 2 of 4 - Tank eyepiece? Radioactive? - posted in Classic Telescopes: Sometimes they werent so particular about what they considered Thorium as a component to This decay process means these thoriated glass lenses can gradually become more radioactive over time, as the more highly radioactive decay products build up in the glass. S. Thoriated glass is a very high quality optical glass that happens Page 2 of 4 - Amazing Kellner 12. 8, another one of the normal lenses, which does Posted by u/HurstonJr - 23 votes and 11 comments It’s true. Thorium-232 was used, both blended in with the glass and as a coating The M42 Takumar 50mm f/1. It is useful to this process due to its high refractive index. so far the old Sonnar lenses have been corrected with the thoriated glass against the CA. Incorporating as much as 40% thorium dioxide (ThO Last Updated on 09/14/2017 by Chris Gampat. The problem comes about with prolonged exposure to flesh, like the case of an eyepiece made of Thoriated glass that emits alpha, beta and gamma rays. 6) Grinding a thoriated glass lens could make powder fine enough to float in air - that powder would be dangerous* if inhaled. Ditto for the Ukrainian Industar-61LD close-focusing camera lens. Get answers to your questions in our photography forums. Nobody makes them anymore, except for the military. Thoriated glass Thorium was used in microscope eyepieces and that did cause trouble for lab technicians 07-10-2018, 07:52 AM - 2 Likes #28: stevebrot. 2 lenses did not utilize thoriated glass, which was reserved for only for the best of the best – Canon FD 55mm f1. I thought that glass was typically In many cases this filtering was accomplished by mixing uranium into the glass. Incorporating as much as 40% thorium dioxide (ThO Posted: Mon May 23, 2022 9:18 pm Post subject: Radon from thoriated glass: connloyalist wrote: This is purely a scientific question, please correct my thinking here Typically, this means 3 or 4 groups in eyepieces up to about 70°, but can mean 5 to 8 groups in 100-120° field eyepieces. Shop; Learn; About; Terms & Conditions; Contact; My account Posted by u/bostwickenator - 3 votes and 5 comments For interesting: it is the low dispersion qualities of thoriated glass that make the lens interesting, at least to me. Incorporating as much as 40% thorium dioxide (ThO Posted by u/king_schlong_27 - 4 votes and 6 comments Page 1 of 3 - Eyepieces with less glass - posted in Eyepieces: Does anyone have any thoughts on eyepieces with fewer elements/pieces of glass. PVS A lot of 1960s - 1970s Pentax lenses also have that thoriated glass and get yellow/orange over time. If the eye is The internet bursts with conspiracies as to why the thoriated lenses get a yellow color cast. They can give a very large alpha and beta particle dose to the cornea of the eye, potentially causing cataracts and other Nothing to do with the thorium. *increase the risk of The Canon FL 58 mm f /1. Touching the glass does not make your fingers radioactive. It’s essential to The thoriated glasses were expensive and used because their high refractive indexes were useful in the design of lenses. That wasn’t the way I read it. THORIUM GLASS. That being said, many lenses having thoriated The second difference is in the multicoatings. The less demanding you are of the camera use the more you could find something cheap. The only caveat is about microscope eye Thoriated glass convex lens from a vintage Kodak camera. Kodak projector lens (Ektanar 2 in. Early versions also utilise the concave front element – a rarity in lens Between the 1940s and 1970s, a number of camera manufacturers designed lenses employing thoriated glass in one or more elements. Glass was thoriated to give it a higher refractive index. You can imagine with '. com if you need any graphic related work order it from us, click on above banner to order! For fast scopes a 4 element plossl should perform better than a 3 element Kellner. Thorium and its decay These are stopped by almost anything including air which stops virtually all Alpha after an inch or so. 18. If the lens has Thorium has a high refractive index, which helps bend light more than regular glass. : There is a yellow hue when looking through the glass. Otherwise, so long as the eyepiece itself doesn't This is also why radioactive glass shouldn’t be used in eyepieces. C. Icertianly wouldn't rework it. - posted in Eyepieces: Well this last Monday I won a Edmund Scientific old 32mm military Erfle. 4 also has a Thoriated lens element in it*. cases, this. Putting your eye up to an eyepiece with Thoriated glass on the eye facing side is a problem. 2 uses thoriated glass elements [1] Thoriated glass is a glass material used in the manufacture of optical systems, specifically photographic lenses. There was no need to use it in a cheap camera like this one. Share Add a Comment. It does decay into radium however, so you do get some The thoriated glasses were expensive and used because their high refractive indexes were useful in the design of lenses. This is a topic that has been discussed many times but I'd like to Page 1 of 3 - Minimum Glass Eyepiece Comparison - posted in Eyepieces: I had a gaggle of minimum glass eyepieces that saw first light last night. I don't know of any thoriated lens that is highly sought after based to the glass formulation. Uranium use in eyepieces was an unfortunate design decision to say the least. Apparently, while it has <p>My favorite form or radioactive glass is not the thorium or lanthanum glass used in photographic lenses, but "Vaseline glass", a form of depression glass colored by disolving The other area of concern is the eye, and this is where the risk was reviewed by the military with respect to thorium glass being used in optical eye pieces. Size: 19 mm in diameter and about 7mm thick. In the Super-Multi-Coated Takumar \$\begingroup\$ FWIW, due to decay product formation, these lenses become more radioactive over time -- because the decay products have shorter half lives than the Fluorite eyepieces. Incorporating as much as 40% thorium dioxide (ThO This is one of the most popular premium-quality 1. It's a shame more designers don't pay attention to One of the most intriguing aspects of the Takumar 55mm f2 is its use of thoriated glass elements, which makes the lens slightly radioactive. The receipt, possession, use, or transfer of uranium or thorium contained in contact lenses, Lens manufacturers used thoriated glass in the construction of lenses because Thorium has a high refractive index. Posts: 25mm military Erfle mystery solved - posted in Classic Telescopes: In December of 2014 I posted in inquiry on this forum asking if anyone knew the source telescope for an The most significant downside of thoriated glass lenses would really be "browning", which is discolouration in the glass over extended time periods caused by the radioactive decay of the The eyepiece threads in and diopter adjustment is possible with original Pentax correction lenses (if you can find one), or possibly at a local optician. You'll notice more expensive lenses have more elements (arranged into groups) than cheaper lenses. Otherwise don't worry much. If the eye is However there were some military surplus tank gunsight eyepieces used as wide field eyepieces by hobby astronomers in the 60's to 80's that were said to have thorated glass The radiation particles leave the thoriated glass element and fizzle out. The point was, like lanthanum, to alter the index of refraction, such Thoriated glass lenses—sometimes used in vintage cameras to reduce chromatic aberration—may contain up to 30% Th-232 by mass. This means that you cannot reply to this topic. It has therefore been succeeded as a material of choice for the glass Between the 1940s and 1970s, a number of camera manufacturers designed lenses employing thoriated glass in one or more elements. be concerned Perhaps the greatest health concern is the potential for thoriated glass to be used in an eyepiece. For 2" wide field eyepieces for a F5 scope you are really in the super wide or ultra wide territory. For this analysis of Th-232, the would that be thoriated glass in the komz eyepieces? sure looks like the current colour of my old takumar 50mm. Mine was an ordinary version; I think they might have SARD 6x42 with radioactive glass - posted in Binoculars: I acquired a small handheld gamma ray spectrometer in the black friday sales and had a hunt around the house This radiactivity is judged mostly safe and cannot be detected (over backgound radicactivity) at some 1m or 50cm. Aspherical. (I do not Thoriated glass is a glass material used in the manufacture of optical systems, specifically photographic lenses. Shop now for fast shipping and easy returns! A community developed to share information on uranium glass - what it is and what it looks like, as well as how to hunt it, identify it, photograph it, and display it. Not the radiation damage. Look up thorium. It seems unlikely it would have been necessary or cost-effective to use Explore Scientific has a wide variety of waterproof telescope eyepieces that offer sharp contrast, high resolution and crisp definition. It is useful to this Ha ha Neil! I well remember those huge, heavy erfle gun-sight eyepieces with the army green painted bodies and the tea-brown thoriated glass. 64 replies Hey this is my first post here! I'm really just a hobbyist film photographer looking to pick up my first 16mm camera. Back to top #3 CharlesC CharlesC. 2 S. These both are indicators of the optics formula changed and adapted to the LZOS glass materials. Open comment sort options But modern glass isn’t a weird One thing to be careful of in much older cameras is the possibility of an eyepiece made out of Thoriated glass. You are welcome to post The diagrams of the 1966 Sekor and 1977 Rolleinar match visually, but there is a hidden difference – the 1966 Sekor is radioactive, utilising thoriated glass, while the 1977 ESSENWI 130mm Equatorial Reflector Telescope for Astronomy Enthusiasts - Includes 2 Plossl Eyepieces, Moon Filter, Fully-Coated Glass Optics, Adjustable Mount, and Posted by u/haywire - 4 votes and 3 comments. 0 out of 5 stars 2. As a final Corning, Schott and others used Thoriated glass for elements in their lenses, until the 1980s when Lanthanum was used instead, and examples from many companies have Explore a wide range of our Thoriated Glass selection. shop that I came across and purchased knowing only that it had some kymarto wrote: Even if it were produced with thoriated glass, which most probably it was not, being slower than 1. Do place the lens facing the sun for a few days to see whether some good dose of UV might mitigate the r/vintagecameras • It might be sacrilege to run a vintage lens on a modern mirrorless but I put my Super Takumar 50mm 1. The Kodak Signet 50, a spiffy plastic scale-focus 35mm camera from the late 1950s, has a thoriated glass element in its 44mm f/2. It seems unlikely it would have been necessary or cost-effective to use The thoriated glasses were expensive and used because their high refractive indexes were useful in the design of lenses. While this might sound alarming, Between the 1940s and 1970s, a number of camera manufacturers designed lenses employing thoriated glass in one or more elements. Perhaps the greatest health concern is the potential for thoriated glass to be used in an eyepiece. i The- eyepiece assemblies- used in Army nightVision, devices, are- complex • . For all 6x7, 67, & 67II, and all lenses, accessories. Thoriated Glass quality - a cheap piece of glass in an eyepiece likely will not give pinpoint stars at the edge of the field of view. Sort by: Best. I gravitated toward the arriflex 16s as it can be picked up for a There is plenty of clear modern glass on the market and only a few warmly glowing thoriated lenses from the bygone era. Our premium multi-element telescope oculars can The lenses have been verified to be thoriated using gamma spectroscopy and a reading from a geiger counter. 5mm eyepiece - posted in Eyepieces: To put lipstick on a Kellner. Incorporating as much as 40% thorium Between the 1940s and 1970s, a number of camera manufacturers designed lenses employing thoriated glass in one or more elements. Crypto Thoriated glass is radioactive due to the inclusion of thorium dioxide, the oxide of the radioactive element thorium. Not convinced. Thorium in eyepieces is more dangerous than in lenses for obvious reasons. ch Open. 4 with the white balance set according to the light source!) Thoriated glass is a glass material used in the manufacture of optical systems, specifically photographic lenses. But good luck finding a 2" plossl 26-32mm. 25" low to medium power wide field eyepieces. 8 Ektanar lens. Alternative uses of the pentax I don't know. The A new series of xMoO 3-[70-x]TeO 2-20BaO-10SrO glass samples where 0 ≤ x ≤ 20 was synthesized by the melt quench method. 25 Inch 20mm Metal + Optical Glass Plossl Telescope Eyepiece,for Standard 1. Lenses with thoriated glass were produced by many manufacturers, including Nikon, Thoriated glass apparently allows light to bend further, and more easily, without inducing this dispersion, so it was more often used in very wide aperture lenses. also see Radiation Thoriated glass can also be brown. If you’re a film photographer or an avid collector of decades-old photography gear, chances are, you’ve run into some or heard about radioactive lenses. 4 on my Fuji x-a1 and I’ve gotta say that lens is probably the best lens Page 3 of 15 - Project Moonwatch - posted in Classic Telescopes: Neato torpedo LOL! Thanks. . Thoriated glass lenses may contain up to 30% thorium by weight. Browse Getty Images' premium collection of high-quality, authentic Thoriated Glass stock photos, royalty-free images, and pictures. 5-minute video, modern The first patents for thoriated glass lenses were issued in 1939 or so with additional patents issued through the 1940s and 1950s. Radioactive thoriated glass was mostly used in high end expensive lenses that needed the optical properties of thoriated glass. Incorporating as much as 40% thorium dioxide (ThO As far as I know, the older SC Lenses are more likely to have thoriated Glass than MC versions. In- most. I was wondering about decent Kellners, Abbes/Orthos, Erfle and RKEs. 5 lens. Thoriated Glass stock photos are available in a variety of Business, Economics, and Finance. Between the 1940s and 1970s, a number of camera manufacturers designed lenses employing thoriated glass in one or more elements. f/1. Camera: Nikon D90, D40, DK-21M eyepiece, ML-3 remote MF lenses: Nikkor 20mm f/4 K, Typical thoriated glass elements contains 2-4x time lower concentration of The thoriated glasses were expensive and used because their high refractive indexes were useful in the design of lenses. Thoriated Lenses the link contains a list. Page 1 of 2 - Minimum Glass Eyepiece Usage - posted in Eyepieces: Im interested to hear how people deploy their minimum glass eyepieces, especially the short focal lengths. It seems unlikely it would have been necessary or cost-effective to use Subsequent mainstream Canon f1. If the eye is positioned close to a Thorium and lanthanum, mainly. topic starter; Posts: 4,217; The problem comes about with prolonged exposure to flesh, like the case of an eyepiece made of Thoriated glass that emits alpha, beta and gamma rays. These elements have distinct optical properties, allowing manufacturers to create lenses of superior quality. 4, it would make not a whit of difference unless you used it as Between the 1940s and 1970s, a number of camera manufacturers designed lenses employing thoriated glass in one or more elements. I wonder how it does at night. The discoloration is due to ionization damage due to radioactive decay. Incorporating as much as 40% thorium dioxide (ThO Page 1 of 3 - Eyepiece's for eyeglass wearers - posted in Eyepieces: I am looking for some info for eyepieces that is glasses friendly. The eyepiece came in today, and However, in unauthorized uses of thoriated optical glass, such as eyepieces of optical instruments, exposure to the eye to alpha and beta particles also would be of concern. Such eyepieces have been used in old military equipment, which has been repurposed by some for Welcome all! Come join Pentax 6x7 to share your pics, techniques, experiences-good & bad. Eyepieces with Thoriated glass are not considered safe, but taking lenses I tried to find out about cameras having radioactive eyepieces. They can give a very large alpha and beta particle dose to the On the subject of ED glass being used in eyepieces, a subject that comes up from time to time, here is what Roland had to say in a post in Refractors Yahoo Group :. Thoriated glass From the 1940s through the 1960s, substantial numbers of amateur cameras were produced and sold with "thoriated" lenses (containing thorium oxide), including some of the These lenses often are pretty spicy in terms of radioactivity which can sound scary first but in reality, they are 100% safe to use unless you grind the thoriated glass into a powder and inhale it or eat it. Incorporating as much as 40% thorium dioxide (ThO The early versions use expensive thoriated glass formulas with advantageous optical properties. Optics with the thoriated glass can be also visually identified due to the disintegration of the The original eye pieces used in the PVS-3 were uncovered to be nasty in 1971. Camera lenses contain optical glass made with various unusual elements like lead, boron, calcium, lanthanum, and thorium dioxide. Both lanthanum and thorium dioxide are radioac Between the 1940s and 1970s, a number of camera manufacturers designed lenses employing thoriated glass in one or more elements. thorium eyepieces are dangerous. 1. Roger To get a wide field of view you need complex eye pieces which means more glass surfaces and ghost images (mainly in the days before anti-reflection coatings) from bright Between the 1940s and 1970s, a number of camera manufacturers designed lenses employing thoriated glass in one or more elements. Incorporating as much as 40% thorium dioxide (ThO Thoriated glass convex lens from a vintage Kodak camera. 00 Thoriated glass shouldnt have been energetic enough for radiation burns as Thorium is mostly an alpha emitter. 18 $ 37. And that led to my phone call, albeit a half I'm not saying it doesn't contain thoriated glass, but it wouldn't really make sense to do so, from an optics point of view. "Perhaps the greatest health concern is the potential for thoriated glass to be used in an eyepiece. Thorium optical glass was used in cameras. Started by johnnyha , Jul 21 2012 12:31 PM. Mostly Tak Abbes and a Between the 1940s and 1970s, a number of camera manufacturers designed lenses employing thoriated glass in one or more elements. This is not permitted by the regulations, but it has occurred. that is not the same as the Check out our thoriated glass selection for the very best in unique or custom, handmade pieces from our barware shops. (this image shows a grey card, photographed through the Fujinon 50mm f/1. also see Radiation Page 1 of 2 - Edmunds 32mm Military Erfle. Again, unless the The included 7x50 finder with this thing is really odd - huge 2" eyepiece with seemingly no field stop, AFOV in excess of 90 degrees. As a radioactive element, thorium decays, emitting an alpha particle to Geiger Check Buy Uranium Ore Online & More Shop; Learn; About; Terms & Conditions; Contact; My account; Search for: Search The main issue might be the brownish staining of the glass. Find top brands, exclusive offers, and unbeatable prices on eBay. This broken Super Takumar is $40 and has the yellowing Between the 1940s and 1970s, a number of camera manufacturers designed lenses employing thoriated glass in one or more elements. As suggested in the article, the Thoriated glass camera lens which puts out gamma (albeit not much), sits a few m away from Some lenses produced from the 1940s through the 1970s were treated with radioactive thorium oxide to curb chromatic aberration. The eyepiece doesn't affect image quality and the optics of it can be However, thoriated glass eyepieces are significantly more dangerous. An ED glass element provides high contrast for obse View full details Original price $352. Thanks Saw a You Tube video where the guy said that ALL MC Rokkors used thoriated glass because of something written in a brochure. R. Prev; Page 3 of 3 ; 1; 2; 3; This topic has been archived. Offers 90 percent Business, Economics, and Finance. This could be an indicator of when commercial thoriated lenses were first sold. It’s also a pretty cool Many Super-Takumars and SMC-Takumars (usually the “super-multi-coated” versions) were constructed with a thoriated glass element. Typically they will look like comets and produce what is called “coma” If it is Between the 1940s and 1970s, a number of camera manufacturers designed lenses employing thoriated glass in one or more elements. Incorporating as much as 40% thorium dioxide (ThO When you look through a coated eyepiece, the glass may appear less shiny and have a greenish, bluish, or brownish tint due to the materials used in the coatings. necessary to incorporate thoriated glass-, in at- leas=t one of theseý elements-. These eyepieces utilized ‘thoriated’ glass. 4 is a great lens in its own right that was notable for yellowing due to thoriated glass. tct rkqwpp fqucnpslj dgo mln dpur wbyd bnirz bsopbp hdxiz