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Junior

The very underestimated problem of RADIOACTIVE lenses

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Hi!
It's one of my first posts here but not the funniest I guess…
I'm not especially talking about a magic C-lens in particular here but about a very underestimated question: radioactive lenses!
One of my friends is a fireman captain and introduced me yesterday to one of his colleagues specialized in technological risks and chemical dangers (at Poissy, France : they're known to have very great equipments.) We made 3 different tests on all my Russian lenses which are all OK excepted the Mamiya Sekor 55mm f1.4 (M42).
Here are the results:
From 5 to 10 µSV per hour (by direct touch), and 1720 shocks per second.
Element involved is Thorium 232.
They told I really shouldn't keep it. Work with it more than one hour is dangerous. It must be gifted to specialized services and absolutely not be destroyed! Or thrashed! The most dangerous exposure isn't even radiations but dusts to inhalate or ingerate (when a lens gets old it disaggregates - it's something you can't always clearly see).
I'm lucky cause until today I kept it in my basement.
So, say it please to your friends and all potential Mamiya/Takumar users that you know via websites etc, it's a strong matter of health.

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EOSHD Pro Color for Sony cameras EOSHD Pro LOG for Sony CamerasEOSHD C-LOG and Film Profiles for All Canon DSLRs

you get more radiation on a long haul flight of 10 hours and more radiation to your face from a dental xray than you do from an old lens

 

I would not worry about this too much , store your lens in a metal box or just wrap aluminium foil around it while you are not using it.

 just dont go licking the lens that would not be good!!!

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Pilots and hostess have cancer increase. Radiologists are really protected and supervised). You Andy take plane maybe 5 times a year and go to the dentist (for x-rays) maybe once a couple of years, for 30 seconds. You can't compare! Aluminium won't help, just concrete or lead. Radioactive lenses is a very UNDERESTIMATED problem, espescially on photo forums. I know what told the geiger and the officers. I think we talk about health here, not bokeh.
 

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if getting radioactive poisoning is what it takes to use interesting glass I'll take the risk thanks:)   If someone told me to eat the lens you mention, I'd give it a go as long as it was medium rare and not overdone.  a couple of button mushrooms, some chips and maybe a side garnish of horseradish sauce. - And if anything I'd end up more healthy.  Boom.  

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That's very interesting.. what do you know about Zeiss C/Y lenses? Apparently it's in the glass itself.

 

some vintage ones on the list:

 

Konica Hexanon 57mm f1.2

 

Bell & Howell Director Series (Model 1208?) XL Super 8 movie camera; Zoom Lens f: 1.2 F: 9-22.5 mm
 
Carl Zeiss Jena Pancolar 55mm f1.4 (measured at 2360 nSv/h)
Carl Zeiss Jena Pancolar 50mm f1.8 "Zebra"
Carl Zeiss Jena Biometar 80mm f2.8 "Zebra" "(Only P6 mount version )
Carl Zeiss Jena Flektogon 50mm f4 "Zebra" "(Only P6 mount version ) YouTube
Carl Zeiss Jena Prakticar 50mm f1.4 (1st version with engravings around the outer side of barrel)

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10 μSv is the dose everyone just got from background radiation in the last 24hrs.

 

So 1 hour of cuddling the rear element of your radioactive lens = 1 normal day living on earth.

 

Just after Fukushima I went to Japan.

 

People there over the entire year had a 1,052 μSv dose of radiation based on Tokyo's readings.

 

That is still only 2% of what the US allows workers to receive per year at work!

 

Source: http://www.blacksmithinstitute.org/blog/radiation-101-what-is-it-how-much-is-dangerous-and-how-does-fukushima-compare-to-chernobyl/

 

So say you spent 5 hours shooting with your radioactive lens per day, EVERY DAY of the year. That is still only 1825 Î¼Sv exposure and still under 5% of the total limit which is considered 'safe' by the US authorities.

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...yes but radiation acts accumulatively, so travel to japan+daily radition from all electronic devices+a few trips with an airplane and x-ray 

add a few radioactive lenses lying around the house..equals who knows what

 

dont know about you but if you have small kids or any pregnant ladies around, i wouldnt be so keen on keeping them.

and i think people should know which ones are radioactive...please add more in the list if you know any.

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10 μSv is the dose everyone just got from background radiation in the last 24hrs.

 

So 1 hour of cuddling the rear element of your radioactive lens = 1 normal day living on earth.

 

Just after Fukushima I went to Japan.

 

People there over the entire year had a 1,052 μSv dose of radiation based on Tokyo's readings.

 

That is still only 2% of what the US allows workers to receive per year at work!

 

Source: http://www.blacksmithinstitute.org/blog/radiation-101-what-is-it-how-much-is-dangerous-and-how-does-fukushima-compare-to-chernobyl/

 

So say you spent 5 hours shooting with your radioactive lens per day, EVERY DAY of the year. That is still only 1825 Î¼Sv exposure and still under 5% of the total limit which is considered 'safe' by the US authorities.

 

Andrew, our body receives a natural telluric daily dose of 0,5 μSv per day. If you add to this natural one, the industrial, medical, cosmical etc it makes approximately 2,4 mSv/year (people get unequally 1,5 to 6,0 mSv/year in France - official numbers! Check it: http://www2.cndp.fr/themadoc/radioactivite/radioactiviteimp.htm ).

 

What the specialised guys told me yesterday is that even if it doesn't stay around your neck or on your chest for hours, (or under your bed), it's still dangerous because of lost dusts. One of the main risks is to let it fall and break it for example. Vacuum cleaner wouldn't help you there…

Once ingerated (accidentally of course), Radium 226 is known to stay on bones and in liver for life!

 

Maybe you think that if all this was true it would be a more widely reported issue? I agree, but you need to know that the famous firemen department where I was yesterday has just added my Mamiya in their "hot" database. Think about it. I've sent them some other links cause they asked me for. I don't know why it's not much more a reported issue… but it should be!

I had enough of contradictory forums that's why I took a train to get personnaly a real specialist. We made 3 different test and they were all very bad (results are in my top post). Takumar f1.4 is known to be worse than Mamiya, so what I say comes from pros, not from this rich but unreliable world wide web. Anyway, each one is free.

 

If it can help, my clean checked "vintage russian lenses" are:
- Helios 44m;
- Tair 11A;

- Jupiter 9 ;
- Mir 24M.
My Sankor 16D is clean too. (And modern lenses aren't concerned.)
Take care of 70's russian lenses.

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Look around where you live and work each day.  Are your walls white?  There's a fair chance you're being irradiated by the titanium in the pigment in the paint, depending on the source.  And anything else painted white or with white pigment.

 

Back in the '80s and '90s my dad worked as a chemist.  One of his last jobs was as a pigment specialist for this company that, among other things, made an alternative to the titanium-based white pigments used in everything from paint to plastics to food.  He came home rattled one night because while the company tried to sell customers their product they still did a lot of color matching formulation for all kinds of products and still did a fair amount of work with titanium and they got a particularly "hot" batch from China that somehow made it through Customs and was sitting on a barge.  Nobody knew what to do with it that wasn't going to amount to an international incident.  

 

He knew that much of the time the metal had trace amounts of radioactivity but it was within EPA standards.  This was apparently closer to nuclear fallout level stuff that only got found out because someone got curious.  Who knows how much had already come in like that or would come in like that in the future.  I was told not to talk about it with any of my friends at school and we never really talked about it again.  I still don't know what happened to the barge full of the stuff but I think about that night every time I stare at a white wall or something made of white plastic.

 

I'm not worried about these lenses. 

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...yes but radiation acts accumulatively, so travel to japan+daily radition from all electronic devices+a few trips with an airplane and x-ray 

add a few radioactive lenses lying around the house..equals who knows what

 

dont know about you but if you have small kids or any pregnant ladies around, i wouldnt be so keen on keeping them.

and i think people should know which ones are radioactive...please add more in the list if you know any.

 

When the geiger became noisy yesterday, firemen asked me first if I had kids or animals. They're really vulnerables.
 

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Oh, and Thorium 232, if that's in fact what's involved, a single sheet of paper shields you from alpha particle decay, even very energetic alpha particles.  Since you aren't holding the lens itself to your eye but you have a camera body and all kinds of materials and surfaces between you and either the rear or front element you're shielded.  If it's got front and rear caps on, you're shielded.   If it's in a box under your bed, you're shielded.  If it's wrapped in paper and tucked under your pillow, you're shielded.

 

Even if it were a different variety of Thorium that gave off beta particles, they're shielded by aluminum, plastic, wood, water, etc.  With no reason for bare skin contact with the lens you're almost always in a situation where you're shielded during use, storage or transport.

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from wikipedia, or course:

 

Thorium dioxide was formerly added to glasses during manufacture to increase their refractive index, producing thoriated glass with up to 40% ThO2 content. These glasses were used in the construction of high-quality photographic lenses. However, the radioactivity of the thorium caused both a safety and pollution hazard and self-degradation of the glass (turning it yellow or brown over time). Lanthanum oxide has replaced thorium dioxide in almost all modern high-index glasses.

 

and this:

 

 it was found to be a carcinogen, sometimes causing cholangiocarcinoma  (that is with respect to another use for thorium dioxide in the past, as an x-ray contrast agent).

 

I'm not really concerned about 90% of my lenses, but I was just working on an old rangefinder lens, including taking apart the elements and removing fungus, so this is good to know. My main concern wouldn't be beta rays but just doing something stupid like shattering a lens trying to re-glue it or something. Not likely, but I'm going to check if thorium dioxide was used in glass before I work on it now. Thanks for the post junior.

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Guest Ebrahim Saadawi

Hi!
It's one of my first posts here but not the funniest I guess…
.


Guess again.

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Guest Ebrahim Saadawi

Funny thing is I've been a physician for 40 years, with a PhD in Radiology for about 30, so I know a thing or two about radioactivity, and the extent of danger on us...

Technically, are there risks? Yes. Just like there are risks of getting hit by a bus everytime you're walking down the street,

like there are risks of getting poisoned everytime you get an x-ray,

just like there are risks of getting rejected everytime you ask her out :)

Just don't eat your hundred year-old lenses everyday for next 20 years, and you'll be fine, happy shooting people!

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