Thorium lenses
Web10 CFR 40.13(c) (7) Unimportant quantities of source material. (7) Thorium or uranium contained in or on finished optical lenses and mirrors, provided that each lens or mirror does not contain more than 10 percent by weight thorium or uranium or, for lenses manufactured before August 27, 2013, 30 percent by weight of thorium; and that the exemption … WebJul 19, 2024 · The Mamiya-Sekor on the other hand is entirely metal, is a fast f/1.4 lens, and yet still weighs in at a mere 305g. It also looks almost diminutive in comparison. As a manual focus lens, the focusing ring is very smooth with a fairly wide throw, and the aperture ring is pleasant with palpable and audible clicks at each half-stop.
Thorium lenses
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WebJul 26, 2015 · Hi. I recently bought one of the radioactive Takumars (50mm f/1.4 Super) and it's clearly yellow due to the thorium content. Well, I removed the caps and covered the lens in aluminium foil (obviously not the front lens area) like some people have advised not to warm the lens too much in sunlight. WebApr 11, 2024 · Thorium (Th) is a naturally ... These analyses were performed using the available experimental setup at the INE-Beamline using polycapillary half-lenses to achieve an X-ray beam footprint of about ...
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. WebOriginal – "Some older photographic lenses were produced with glass elements containing small amounts of thorium. If stored in the dark for prolonged periods of time, these …
WebOct 11, 2012 · YouTube user uyt384 does tests on old camera lenses, but not in the way you'd expect. ... (S-M-C Takumar), well known for its radioactive thorium glass element near the rear of the lens. WebAug 7, 2024 · A 100% thorium lens would have a different radioactive output than a glass lens with 1 PPM of thorium in it. Report comment. Reply. Murray says: August 7, 2024 at 2:50 am
WebJan 27, 2024 · Radioactive lenses. Many lenses produced from the 1940s through the 1980s are measurably radioactive. The main source of radioactivity is the use of thorium oxide …
WebJul 28, 2024 · When the thorium begins to decay, it discolours crystalline gaps at an atomic level (Farbe centers), and once transparent glass turns brown (sends auto white balance into a hissy fit, and produces a rather sickly tint if you don’t swap to’K’. Off-topic, but the Thorium in this lens is often reported on the internet as relatively harmless. craziest minecraft seeds bedrock editionWebSimply, thorium allowed the lens manufacturer to produce high quality lenses at a reduced price. its optical properties of high refractivity and low dispersion allowed lens designers to minimize chromatic aberration and utilize lenses of lower curvature. Lanthanum was also used. Lanthanum has very weak radioactive properties, if any. dkny relaxed aline shape sweaterWebOct 1, 2024 · 💀100% WRONG. Facts about Thorium lenses. Its neither a coating NOR merely ALPHA emitter FACT: The only naturally occurring isotope of thorium is 232Th and i... craziest minecraft seeds bedrockWebAug 29, 2024 · Multi Format. Aug 28, 2024. #2. Thorium emits alpha radiation. In air, alpha radiation can travel about an inch or so and cannot penetrate human skin so thorium lenses are quite safe to handle. Should you eat your lens then it is a very different matter as alpha radiation inside your body is rather dangerous. craziest laws in paWebApr 26, 2014 · Thorium dioxide was formerly added to glasses during manufacture to increase their refractive index, producing thoriated glass with up to 40% ThO 2 content. These glasses were used in the construction of high-quality photographic lenses . craziest medal of honor storyWebSep 11, 2024 · The options are either professional lens modding by a company like CinMod, or trying a DIY solution with one of the kits available. Canon FD Thorium Yellow Tint. … craziest music videos of all timeThoriated 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… dkny relaxed straight jeans