WebAug 10, 2009 · Some lenses known to contain thorium oxide in the glass do not emit enough radiation to become yellow, but it's still more than background level radiation. Apparently, the use of thorium oxide was abandoned by Japanese SLR lens makers by the mid-1970's. Those makes that did use thorium oxide in some products also made … WebFeb 2, 2005 · The reason camera companies stopped using Thorium in lenses has nothing to do with radioactivity. 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 paperweights in the 80s and 90s, when color became the dominant lifeform in photography.
Flight armor - Thorium Mod Wiki
WebOct 8, 2024 · At the same time, the properties of thorium help to reduce the dispersion of different wavelengths of light (the different colors) as they pass through the glass. The … WebOct 8, 2024 · Of course, any lens could benefit from the addition of thorium, and after the war ended it started finding its way in to consumer products – primarily into lenses for high-end cameras. Over the years a number of manufacturers began making thoriated lenses, a practice that continued into the 1980s. early test for dementia
A Radioactive Lens PetaPixel
WebOnce a pilot has fully recovered with a fixed lens and meets FAA vision standards, they typically may return to flying on their current medical. Note, however, that in Sep 2014 … WebAug 22, 2024 · Ghery Pettit. I've been using progressive lenses for over 25 years. No problem at all with flying, other than when wearing foggles for instrument flying. Darned foggles wipe out the part of the lens that focuses on the radio stack, so I can't see the count-down timer on the 430W. Other than that, no problem at all. WebDec 9, 2010 · Canon did have "Flourite" lenses - these had a green band around the hood (if there was a built in hood) - and were marked flourite on th ename ring. Flourite lenses ar enot common - there was a 24mm which I've never seen, a 55/1.2 which they made around 350 off, plus the 300/2.8 flourite. These are all old FD mount. csulb digital marketing bootcamp cost