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Question about radioactivity..
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PostPosted: Wed Jul 07, 2010 10:58 am    Post subject: Question about radioactivity.. Reply with quote
Hey, I was all siked to get some old lenses, but when I heard about radioactivity I got worried. I'm a real hypochondriac when it comes to weird stuff like this. Anyway I got a couple of questions about it

Why do the old lenses have radioactivity in them?

What can radioactivity do to you?

How much is too much when it comes to the lenses? I.E. when does the amount get dangerous, say I'm carrying like 4 or 5 rated at 200 in my bag, is that dangerous? Also, how long would you have to be exposed to it for it to affect you or anything...

Do modern lenses (the cheap plastic AF ones) have radioactivity in them?

Do we get exposed to any radiation in our every day lifes?


What type of radiation is in the old lenses? Is it alpha? If it is I don't see it being able to really harm anything unless you have wounds on your hands or something.

last question: Can a Geiger meter tell if theres Alpha, Gamma/X, and Beta radiation?

So many people use these lenses, and I don't see anything bad happening but I'm still worried about it;;


PostPosted: Wed Jul 07, 2010 11:16 am    Post subject: Reply with quote
Hi. Welcome to the forum.

If you use the Forum search function (top-right of the page) and search for "radioactive" you will find about 90 threads. Some of these are general discussions and have "radioactive" or "radioactivity" in the title. Perhaps these can help you.


PostPosted: Wed Jul 07, 2010 11:30 am    Post subject: Reply with quote
Don't bother about those lenses. There's much more stuff out there, making radioactive emission. Like money, garbage, big cities, industry, cars and even the sun.


PostPosted: Wed Jul 07, 2010 12:31 pm    Post subject: Reply with quote
It's always smart to avoid extra exposure to nuclear radiation if possible, simply because it's potentially damaging. Personally, I follow the ALARA principle: reduce exposure to a level As Low As Reasonably Achievable. For this reason I chose not to buy the Canon FD 35/2.0 SSC with concave element. Not because it's a serious health threat, but I can easily live without that lens and not have the extra exposure.

@vulko: Cigarette smoke is the biggest radiation hazard that humans create in the general environment: http://drs.ors.od.nih.gov/training/sectionf.htm. Compare the numbers to the one at the bottom (from smoking).


PostPosted: Wed Jul 07, 2010 1:20 pm    Post subject: Reply with quote
If you pressed one of those lenses with Thorium-232 against your face for around 20-40 hours, it would expose you to as much alpha radiation as a full set of dental x-rays.


PostPosted: Wed Jul 07, 2010 2:30 pm    Post subject: Reply with quote
AhamB wrote:
@vulko: Cigarette smoke is the biggest radiation hazard that humans create in the general environment: http://drs.ors.od.nih.gov/training/sectionf.htm. Compare the numbers to the one at the bottom (from smoking).


Yes, those ppl always tell the truf Very Happy
National Institute of Health... those guys get money for their research from the goverment, don't they? And those guys do kill tonns of ppl everyday, in Irak, Afganistan, Kosovo, Vietnam, Korea... all over the world. I don't believe in those researches, mostly bullshit. Just for getting attention of all the other stuff, like envading other countries, ecomony issues and such. The same about the global warming, bird flue... To get money and don't let ppl think about the problems in society, economy and politics.

P.S. If you don't believe... well here's an example. You pay a magazine or tv company to place some commercials for your product. Yet what do you want ppl to know about it? The truf? Or some nice stuff that will make them buy it?
just for concideration...


PostPosted: Wed Jul 07, 2010 2:48 pm    Post subject: Re: Question about radioactivity.. Reply with quote
JohnnyC wrote:

What can radioactivity do to you?


It can kill you.


PostPosted: Wed Jul 07, 2010 6:47 pm    Post subject: Re: Question about radioactivity.. Reply with quote
Hi,

JohnnyC wrote:
Hey, I was all siked to get some old lenses, but when I heard about radioactivity I got worried. I'm a real hypochondriac when it comes to weird stuff like this. Anyway I got a couple of questions about it

Why do the old lenses have radioactivity in them?


Not all the old lenses have radioactive elements, only the best performers have them, because of the rare earths used to build some of the optical elements ...

JohnnyC wrote:

What can radioactivity do to you?


The one from a nuclear power plant, can really harm you. The one you can get from several of those lenses together ... Well, almost nothing: the only thing that could be get harmed is ... your wallet, which will loose the money you spent for buying those lenses Wink ...

JohnnyC wrote:

How much is too much when it comes to the lenses? I.E. when does the amount get dangerous, say I'm carrying like 4 or 5 rated at 200 in my bag, is that dangerous? Also, how long would you have to be exposed to it for it to affect you or anything...


dnas already replied to this question ...

JohnnyC wrote:

Do modern lenses (the cheap plastic AF ones) have radioactivity in them?


The cheap plastic AF ones, probably not ... The more expensive, metallic ones, such as the APO-Lanthar, yes (guess the origin of the Lanthar name) ...

JohnnyC wrote:

Do we get exposed to any radiation in our every day lifes?


Besides the one from cigarette smoke, yes, you (maybe i should say we, instead) are exposed to HF radiations from GSM phones and cellular base stations, to HF radiations from WiFi network interfaces, to HF radiations from Bluetooth peripherals ...

JohnnyC wrote:

What type of radiation is in the old lenses? Is it alpha? If it is I don't see it being able to really harm anything unless you have wounds on your hands or something.


Sorry, i'm not a nuclear engineer, i don't know ... But i wouldn't say that my old SMC Tak 50/1.4 is a source of gamma rays, otherwise i would have gotten all the slides i shot with it burned ...

JohnnyC wrote:

last question: Can a Geiger meter tell if theres Alpha, Gamma/X, and Beta radiation?


Don't have any clue ...

JohnnyC wrote:

So many people use these lenses, and I don't see anything bad happening but I'm still worried about it;;


Well, you should read threads a little deeper: i'm one of those people using those lenses and, while it's true that i don't have a greenish skin and spiked ears, i do have some issues with my wallet, because of the stellar prices reached by most of those radioactive lenses Twisted Evil (Takumars, APO-Lanthars, ...)


PostPosted: Wed Jul 07, 2010 7:36 pm    Post subject: Reply with quote
All radioactive lenses should be sent to me for proper storage due to safety hazards. Laughing


PostPosted: Wed Jul 07, 2010 7:38 pm    Post subject: Reply with quote
Blue wrote:
All radioactive lenses should be sent to me for proper storage due to safety hazards. Laughing


Or to me, I need a third hand Razz


PostPosted: Wed Jul 07, 2010 8:05 pm    Post subject: Reply with quote
... Or to me, i have a big bookcase, sorry, a big anti-radiation case ready to be filled Wink ...

Of course, you will pay the postage only (a little price for a great health) ...


PostPosted: Wed Jul 07, 2010 9:48 pm    Post subject: Reply with quote
vulko wrote:
AhamB wrote:
@vulko: Cigarette smoke is the biggest radiation hazard that humans create in the general environment: http://drs.ors.od.nih.gov/training/sectionf.htm. Compare the numbers to the one at the bottom (from smoking).


Yes, those ppl always tell the truf Very Happy
National Institute of Health... those guys get money for their research from the goverment, don't they?
I don't believe in those researches, mostly bullshit. Just for getting attention of all the other stuff, like envading other countries, ecomony issues and such.


I know what you're saying, but there's plenty of research performed elsewhere about Polonium-210 in tobacco plants and cigarette smoke. I posted the link because not many people seem to know about it, so I absolutely don't believe that this research has been published to catch the public's attention in order to scare/mislead them. If anything, the tobacco industry has done a good job at keeping the media quiet about this research.


PostPosted: Wed Jul 07, 2010 9:58 pm    Post subject: Re: Question about radioactivity.. Reply with quote
indianadinos wrote:

The cheap plastic AF ones, probably not ... The more expensive, metallic ones, such as the APO-Lanthar, yes (guess the origin of the Lanthar name)


Wikipedia says: Contrary to often seen statements to the otherwise, lenses containing lanthanum are not appreciably radioactive - lanthanum is only 1/10,000th as radioactive as thorium. Radioactivity in lanthanum containing lenses is due to the intentional inclusion of thorium in the optical glass mix.

So it's not comparable to say, a Super-Takumar 50/1.4 with thoriated element(s). Radioactive glasses have been long banned anyway, so no modern lenses will have it.



indianadinos wrote:

JohnnyC wrote:

Do we get exposed to any radiation in our every day lifes?


Besides the one from cigarette smoke, yes, you (maybe i should say we, instead) are exposed to HF radiations from GSM phones and cellular base stations, to HF radiations from WiFi network interfaces, to HF radiations from Bluetooth peripherals ...


I think JohnnyC meant any nuclear radiation, not just any radiation. Sunlight also is electromagnetic radiation, just as radiowaves/cellphone/wifi etc are.


It's also a misconception that the radioactive (thoriated) lenses are the absolute best ones. It hasn't been proven, for instance, that the early thoriated Minolta Rokkor 58/1.2 is better than the later versions without the thoriated glass. There's too many other examples of great lenses that don't need to use hazardous materials to get incredible performance. Nowadays the lens manufacturers have also banned lead from their optical glasses. Only more advanced materials are available now...


PostPosted: Thu Jul 08, 2010 12:24 am    Post subject: Re: Question about radioactivity.. Reply with quote
AhamB wrote:
Radioactive glasses have been long banned anyway, so no modern lenses will have it.


Out of general curiosity, can you provide a reference to this ban? I haven't been able to find any reference banning thorium in camera lenses, although I suspect that workplace regulations might effectively ban (traditional) manufacture of radioactive lenses due to assembly workers' safety concerns.


PostPosted: Thu Jul 08, 2010 5:30 am    Post subject: Reply with quote
AhamB wrote:
vulko wrote:
AhamB wrote:
@vulko: Cigarette smoke is the biggest radiation hazard that humans create in the general environment: http://drs.ors.od.nih.gov/training/sectionf.htm. Compare the numbers to the one at the bottom (from smoking).


Yes, those ppl always tell the truf Very Happy
National Institute of Health... those guys get money for their research from the goverment, don't they?
I don't believe in those researches, mostly bullshit. Just for getting attention of all the other stuff, like envading other countries, ecomony issues and such.


I know what you're saying, but there's plenty of research performed elsewhere about Polonium-210 in tobacco plants and cigarette smoke. I posted the link because not many people seem to know about it, so I absolutely don't believe that this research has been published to catch the public's attention in order to scare/mislead them. If anything, the tobacco industry has done a good job at keeping the media quiet about this research.

In sixties the researches told that it's very good for health to smoke and doctor recommended. I've seen plenty of posters telling ppl to get a smoke, cause its good for you. I agree, there is a lot of crap in cigarettes, as in other stuff 2. You know, Cola, food from MacDonalds is also very harmful to our health, but nobody tells the truf.


PostPosted: Thu Jul 08, 2010 6:54 am    Post subject: Reply with quote
Welcome to the forum JohnnyC.

Only a small % of lenses out there have minute trace of radiation. If you are uncomfortable with those lenses, you can opt for other lens within the same range. There are plenty to choose from - MF or AF.

For me, everyday I am exposure to more radiation from sunlight, computer, mobile than my lens.


PostPosted: Thu Jul 08, 2010 7:00 am    Post subject: Re: Question about radioactivity.. Reply with quote
JohnnyC wrote:
Why do the old lenses have radioactivity in them?

What can radioactivity do to you?

It's not that they were radioactive by design, simply that some elements, like thorium, were used in small amounts because of the effect they have on the refractive properties of the glass. The amount of radioactivity is too small to be of concern. In order to be affected in any way, you'd have to have the camera with the radioactive glass lens in it pressed to your face for every single minute of two and a half centuries. At the very least this would make you something of a social oddity.


PostPosted: Thu Jul 08, 2010 7:34 am    Post subject: Re: Question about radioactivity.. Reply with quote
Arkku wrote:
AhamB wrote:
Radioactive glasses have been long banned anyway, so no modern lenses will have it.


Out of general curiosity, can you provide a reference to this ban? I haven't been able to find any reference banning thorium in camera lenses, although I suspect that workplace regulations might effectively ban (traditional) manufacture of radioactive lenses due to assembly workers' safety concerns.


I don't really have a solid reference, but I would be surprised if any photographic lenses for the consumer/pro market would still be produced with Thorium or other radioactive elements. I can imagine it could still be in use for some scientific or industrial applications where the lenses would be used in controlled environments.

On this page you see a hint: http://www.camerapedia.org/wiki/Radioactive_lenses#Lenses_with_elements_made_of_contaminated_glass (note on the Minolta Rokkor's).


PostPosted: Thu Jul 08, 2010 8:06 am    Post subject: Reply with quote
I once had the Takumar 50/1.4 and Industar-61 tested by professionals that you can read about here. The radiation is so small that it can't be considered harmful in any way for consumers.

Arkku, it's most likely to protect the workers who assembled the lenses that they stopped producing lenses with radioactive compounds.


PostPosted: Thu Jul 08, 2010 12:22 pm    Post subject: Reply with quote
my_photography wrote:
For me, everyday I am exposure to more radiation from sunlight, computer, mobile than my lens.


All of which have much less energy than the nuclear radiation from Thorium and the other radioactive daughter elements it decays into. UV from the sun can damage your skin, but the rest of the radiation you mention doesn't cause ionisations (cell damage), which nuclear radiation definitely does.

Quote:
As for the radiation, while Thorium 232 is itself an alpha emitter, several of the daughter elements are beta emitters and at least one daughter element emits a high energy gamma ray when it decays (1.2MEV, if memory serves.) With a 15,000 year half-life, Thorium doesn't go away quickly, and with beta and gamma emitters in its decay series, a lens containing Thorium will actually be more radioactive now than when it was manufactured.


From: http://photo.net/canon-fd-camera-forum/00MX58


PostPosted: Thu Jul 08, 2010 2:09 pm    Post subject: Re: Question about radioactivity.. Reply with quote
AhamB wrote:

I don't really have a solid reference, but I would be surprised if any photographic lenses for the consumer/pro market would still be produced with Thorium or other radioactive elements.


I, too, would be surprised e.g. due to the public outcry it would probably cause if a modern lens was discovered to be radioactive. But as far as I can tell, it's still perfectly legal to produce such lenses e.g. in the United States:

http://www.nrc.gov/reading-rm/doc-collections/cfr/part040/part040-0013.html

(See item 7. I can find no reference that this regulation wouldn't be valid anymore.)

AhamB wrote:
On this page you see a hint: http://www.camerapedia.org/wiki/Radioactive_lenses#Lenses_with_elements_made_of_contaminated_glass (note on the Minolta Rokkor's).


Anyone can edit that page; there's no reason to assume that the person who put in that mention of a ban actually knew anything about, well, anything.


PostPosted: Thu Jul 08, 2010 6:53 pm    Post subject: Re: Question about radioactivity.. Reply with quote
Hi,

AhamB wrote:

Wikipedia says: Contrary to often seen statements to the otherwise, lenses containing lanthanum are not appreciably radioactive - lanthanum is only 1/10,000th as radioactive as thorium. Radioactivity in lanthanum containing lenses is due to the intentional inclusion of thorium in the optical glass mix.


Well, don't take this as a personal attack, but i would have preferred an ISBN of a (possibly not out of print) book as reference, since Wikipedia pages are almost editable by everyone ...

lauge wrote:
I once had the Takumar 50/1.4 and Industar-61 tested by professionals that you can read about here. The radiation is so small that it can't be considered harmful in any way for consumers.


I hope that such kind of information doesn't spread too much, the Taks 35/2 and 50/1.4 are becoming extremely expensive Wink ...

Cheers


PostPosted: Thu Jul 08, 2010 7:02 pm    Post subject: Re: Question about radioactivity.. Reply with quote
Arkku wrote:
Anyone can edit that page; there's no reason to assume that the person who put in that mention of a ban actually knew anything about, well, anything.


I suppose that note could have been made by someone like me, who just read about it somewhere. Razz Someone should moderate that page then and point out that it needs references, but I don't care enough. Wink

@Arkku: The US is a special case anyway because they even irradiate their own food to disinfect it. They seem to have a talent for working against nature with their most advanced technology (genetic engeneering etc.).


PostPosted: Thu Jul 08, 2010 7:59 pm    Post subject: Re: Question about radioactivity.. Reply with quote
indianadinos wrote:
AhamB wrote:

Wikipedia says: Contrary to often seen statements to the otherwise, lenses containing lanthanum are not appreciably radioactive - lanthanum is only 1/10,000th as radioactive as thorium. Radioactivity in lanthanum containing lenses is due to the intentional inclusion of thorium in the optical glass mix.


Well, don't take this as a personal attack, but i would have preferred an ISBN of a (possibly not out of print) book as reference, since Wikipedia pages are almost editable by everyone ...


http://www.wolframalpha.com/input/?i=lanthanum-138%2C+thorium-232

(+ add the fact that only 0.09% of naturally occurring lanthanum is of the radioactive ¹³⁸La isotope.)


PostPosted: Fri Jul 09, 2010 10:12 pm    Post subject: Reply with quote
my_photography wrote:
Welcome to the forum JohnnyC.

Only a small % of lenses out there have minute trace of radiation. If you are uncomfortable with those lenses, you can opt for other lens within the same range. There are plenty to choose from - MF or AF.

For me, everyday I am exposure to more radiation from sunlight, computer, mobile than my lens.


Oh, I was under the impression all of the old lenses had it, I'd rather get some lenses that aren't radioactive just to be overly safe. Is there a list or anything anywhere telling which ones aren't / are radioactive? After reading this post I looked it up a bit more and people said Russian glass isn't radioactive, is this true?
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