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Thorium glas

Weboptical glass with thorium in 1949 [1]. This could be an indicator of when commercial thoriated lenses were first sold. Thorium-232 was used, both blended in with the glass and as a coating which gave a higher refractive index as well as a lower dispersion. This resulted in a smaller required curvature of the lenses, hence WebFeb 2, 2005 · Any Thorium based lens turns yellow over a timespan of 20-30 years. So all those great Thorium wides from the 50s and 60s turned into useless, off-color …

Radioactive lenses - Camera-wiki.org - The free camera …

WebAug 18, 2024 · The following is lifted from a file I have on radioactive lenses: "Typical radiation levels can approach 10 mR/hr (100 μSv/h) as measured at the lens element's surface, decreasing substantially with distance; at a distance of 3 ft. (.9 m.) the radiation level is difficult to detect over typical background levels. Web18 hours ago · Das chemische Element Thorium ist ein radioaktives Metall. Es wurde 1828 von dem schwedischen Chemiker Jons Jakob Berzelius entdeckt, der es nach der … palace of galerius https://thephonesclub.com

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WebJan 4, 2015 · A quick demo of a netIO GC10 geiger counter on uranium glass (vaseline glass) and thorium mantles. WebThe Gateway Glass is a Hardmode mirror which can be used to set a temporary gateway and teleport to it. When right-clicking, the user will place a gateway, indicated by a star at that … WebThere are a significant number of lenses produced from the 1940s through the 1970s that are measurably radioactive. Main source of radioactivity is the use of thorium oxide (up to … palace of glass buch

Thorium - Element information, properties and uses Periodic Table

Category:Super Takumar 50mm f/1.4 Lens M42 Questions

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Thorium glas

Vaseline and Uranium Glass (ca. 1930s) Museum of Radiation …

WebThorium can be used as a nuclear fuel through breeding to uranium-233 (U-233). ... lantern mantles, arc-light lamps, welding electrodes and heat-resistant ceramics. Glass containing thorium oxide has both a high refractive index and wavelength dispersion, and is used in high quality lenses for cameras and scientific instruments. Thorium oxide ... WebOct 12, 2024 · Thorium dioxide has a 30-50% higher refractive index than typical glasses which translates into some combination of less-curved (thinner) elements or greater bending of light to produce more compact lenses of a given focal length and aperture. Kodak, Yashica, Mamiya, (and of course, Asahi), among others used thorium glass.

Thorium glas

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http://large.stanford.edu/courses/2024/ph241/kinamon2/ WebNov 7, 2024 · Don't think thorium glass was even used for consumer lenses in the late 70's (when they started making Ai lenses). I also think it was only used in the more complex high end designs - non of your lenses qualify as such. My late 60's Pentax M42 Takumar 50/1,4 does not use Thorium glass, but the earlier first version did.

WebThe sky is perhaps darker than you might normally expect, the glass in this lens is rather yellowed due to radiation damage (thorium glass). The lens is radioactive as hell, but it's fine with a clear glass filter over the front of it. On the back the shutter is enough to stop all the radiation from reaching the film. WebAug 1, 2024 · If you use vintage lenses, you might have heard that some of them are radioactive. As a matter of fact, many lenses produced between the 1940s and the 1970s emit a measurable amount of radioactivity. It comes from the element named Thorium, which was used in the glass elements of the lenses. But should this […]

WebNov 20, 2024 · 'In the light of the above, it is normal for the 1950 Summitar * (star) and the 1951 pre-series Summicron with serial number 92x.xxx to have the classic metamictic … WebMany lenses produced from the 1940s through the 1980s are measurably radioactive. The main source of radioactivity is the use of thorium oxide (up to 30% by weight) as a component of the glass used in the lens elements. Thorium oxide has a crystalline structural similar to calcium fluoride ().Like fluorite, its optical properties of high refractivity and low …

WebThorium dioxide was formerly added to glass during manufacture to increase the refractive index, producing thoriated glass for use in high-quality camera lenses. Production and Price of Thorium. Raw materials prices change daily. They are primarily driven by supply, demand and energy prices.

WebElement Thorium (Th), Group 20, Atomic Number 90, f-block, Mass 232.038. Sources, facts, uses, scarcity (SRI), podcasts, alchemical symbols, videos and images. ... do not travel very far and are easily stopped by the glass cover of a gas lantern and even the human skin. In fact, thorium oxide mantles are still in use today, ... summer camps in richmondsummer camps in seasonWebSep 5, 2024 · Lead, Lanthanum and Thorium glass production were halted as of 2001. For example, the 38mm (Zeiss) Biogon in the (Hasselblad) SWC underwent a slight … summer camps in seattleWebTo confuse matters somewhat, this non-Vaseline glass might even be radioactive due to the presence of thorium impurities! Perhaps the most reliable way to identify the presence of … palace of governors imagesWebAs a compound of high refractive optical glasses, thorium still is present in some professionally used systems-especially in optical equipment with military use. The … summer camps in san antonio txThoriated glass is a glass material used in the manufacture of optical systems, specifically photographic lenses. It is useful to this process due to its high refractive index. Thoriated glass is radioactive due to the inclusion of thorium dioxide, oxide of radioactive element thorium. It has therefore been succeeded as a material of choice by glass including lanthanum oxide. Thoriated glass can contain up to 30% by weight of thorium. The thoriated glass elements in lenses over ti… palace of guizang formulaWebApr 10, 2024 · Thorium is also used in the metallurgical industries in the manufacture of refractory materials. Thorium oxide also finds use in the laboratory cubicles with a high temperature. Thorium, when added to the glass, creates a glass that has a high refractive index and a low dispersion. It is being studied to use thorium as a source of nuclear fuel. summer camps in school