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Radioactive lenses
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PostPosted: Thu Mar 01, 2007 6:51 am    Post subject: Radioactive lenses Reply with quote

A long, very comprehensive, and quite worrying forum message about radioactive lenses.
Sorry, it's italian, but with an online translator you may be able to at least get the overall meaning - and for specific passages, you can ask me:

http://www.photo4u.it/viewtopic.php?p=1530804&sid=c5ec04985b78ebb71e494ca5efa4220f

(I will put the link in the Links forum for a more permanent display)

it seems that not only the well known ones (such as the SMC Takumar 50/1.4) are radioactive. Most of our manual lenses are, especially Nikkors and Leicas (especially Leica Ms). And - to my surprise - it seems that also some Canon EF lenses, still are!

And, it seems that in the SMC Takumar, the back lens actually has Uranium traces in it.

Well, until I read this, I used to keep some lenses in my bedroom (more casually than for a reason). Now, they will go off, and be stored in some place where I know neither me or other people is going to stay for a long time nearer than 2-3 meters.

And I have to lose that habit of keeping a lens next to the computer and play with it while I am working, as a distraction!


PostPosted: Thu Mar 01, 2007 9:41 am    Post subject: Reply with quote

Here's some more stuff on the topic (attention - automated translation - funny results might be possible!):

http://translate.google.com/translate?u=http%3A%2F%2Fphoto.6six6.de%2FYashica_Objektiv_Radioaktivitaet.html&langpair=de%7Cen&hl=de&ie=UTF-8&oe=UTF-8&prev=%2Flanguage_tools


PostPosted: Sun Mar 04, 2007 11:08 am    Post subject: Reply with quote

soem more info in english:

http://www.orau.org/ptp/collection/consumer%20products/cameralens.htm

and a way to fix it:

http://www.hermes.net.au/bayling/repair.html

one may get the suspicion that takumars are not a good idea...


PostPosted: Sun Mar 04, 2007 12:41 pm    Post subject: Reply with quote

goorooj wrote:
soem more info in english:

http://www.orau.org/ptp/collection/consumer%20products/cameralens.htm

and a way to fix it:

http://www.hermes.net.au/bayling/repair.html

one may get the suspicion that takumars are not a good idea...


Laughing

But I think that yellowing is not connected with radioactive glass.


PostPosted: Sun Mar 04, 2007 6:17 pm    Post subject: Radioactive lenses Reply with quote

It should be noted that even for a _serious_ photographer the dose received from a radioactive lens is rather insignificant,
an insignificant fraction of the natural background radiation. Smoking one cigarette per day gives
a larger extra radiation dose due to the radioactive polonium contained in the tobacco.

Veijo


PostPosted: Sun Mar 04, 2007 6:19 pm    Post subject: Reply with quote

Thank you for this answer and welcome aboard! Good to know we are in safety with our favourite lenses. When I started this site mflenses.com I read your excellent tests that was a very good reading, now I am very happy to know you are here with us!


PostPosted: Mon Mar 05, 2007 4:15 am    Post subject: Reply with quote

Attila wrote:
Thank you for this answer and welcome aboard! Good to know we are in safety with our favourite lenses. When I started this site mflenses.com I read your excellent tests that was a very good reading, now I am very happy to know you are here with us!


Thanks Smile, I'll try to drop in every now and then,

Veijo


PostPosted: Mon Jun 04, 2007 6:15 pm    Post subject: Reply with quote

LucisPictor wrote:
But I think that yellowing is not connected with radioactive glass.

It is indeed. The older super-takumars (serial below around 1.4million -i've managed to come to this number after looking to several auctions on eBay; the external differences are subtle) are not radioactive and are -never- yellow. There's explanations and solutions for the yellowing on the internet. I've been trying to buy one of those old takumars so that I won't have a yellowed and radioactive lens, but I think maybe the coating is not nearly as good as the later SMC takumars.
Of course, some lenses are more radioactive than others. I once came across a website where they had measured several different lenses and i've read opinions from some doctor somewhere else... Even if the amount is quite small, it is certainly measurable (several meters apart for the most radioactive lenses) and those lenses are not something you want to keep on your pocket 24/7. I wouldn't even keep them in my desk or in my room all day, just to be safe.


PostPosted: Mon Jun 04, 2007 6:36 pm    Post subject: Reply with quote

maybe they'll give you super powers, like in the movies!

here comes "paperrazzi-man!" Laughing

Tom


PostPosted: Mon Jun 04, 2007 6:42 pm    Post subject: Reply with quote

I had the chance to use a sensitive meter to test for radioactivity and I can tell you about every thing is radioactive. A normal wristwatch is quitte radiactive. I think more then a MF lens. Things to watch out for are old machines to make x-rays. They have a radio active source that is rather dangerous, specially if you open it.

Guido


Last edited by Jigt on Tue Jun 05, 2007 3:26 pm; edited 1 time in total


PostPosted: Tue Jun 05, 2007 9:27 am    Post subject: Reply with quote

My Taku 50 1.4 is a "hotglass" as I know. Its radioactive and has a Thorioum in it. Thorium is the alternative to Uranium Wink. I am planning to buy Industar 61 L/Z which has Lanthanium and is radioactive too.

Soon I will start to Glow beacause I use may taku often Wink


PostPosted: Tue Jun 05, 2007 9:57 am    Post subject: Reply with quote

sqwall wrote:

Soon I will start to Glow beacause I use may taku often Wink


Yes and if everything else fails, we will always be able to resort doing as live road signs Laughing


PostPosted: Tue Jun 05, 2007 10:01 am    Post subject: Reply with quote

Very Happy Thats correct.


PostPosted: Tue Jun 05, 2007 11:08 am    Post subject: Reply with quote

Orio wrote:
sqwall wrote:

Soon I will start to Glow beacause I use may taku often Wink


Yes and if everything else fails, we will always be able to resort doing as live road signs Laughing


So, in a couple of years they will say: "Wait, you can't go. This MF-Lens-Shooter shows a stop-signal!" Wink


PostPosted: Tue Jun 05, 2007 4:43 pm    Post subject: Reply with quote

LucisPictor wrote:

So, in a couple of years they will say: "Wait, you can't go. This MF-Lens-Shooter shows a stop-signal!" Wink


Laughing Laughing Laughing


PostPosted: Tue Jun 05, 2007 6:20 pm    Post subject: Reply with quote

Maybe thats the reason that i lost my hair!!!!

Guido


PostPosted: Sun Dec 27, 2009 9:23 pm    Post subject: Reply with quote

My 180 f2.8 Sonnar P6 has a yellow tinge, although not among the list of radioactive lenses may be so.
Someone knows something? It is the zebra version.
HAppy New Year.


PostPosted: Tue Dec 21, 2010 11:40 pm    Post subject: Reply with quote

goorooj wrote:
soem more info in english:

and a way to fix it:

http://www.hermes.net.au/bayling/repair.html

one may get the suspicion that takumars are not a good idea...


Great, now his garden is radioactive!...I pity his pets and his children, if he has any. Confused


PostPosted: Tue Dec 21, 2010 11:52 pm    Post subject: Reply with quote

Jigt wrote:
I had the chance to use a sensitive meter to test for radioactivity and I can tell you about every thing is radioactive. A normal wristwatch is quitte radiactive. I think more then a MF lens. Things to watch out for are old machines to make x-rays. They have a radio active source that is rather dangerous, specially if you open it.

Guido


Why would an X-ray machine have a radiactive source inside it?
X-ray machines use a Walton-Cockroft multplier curcuit, fed from AC, to produce high voltage D.C....Typically, up to 150,000volts, a radiocative scorce is not required to produce the X-rays...If they do have a source, then perhaps the source is used to calibrate the machine somehow?


PostPosted: Wed Dec 22, 2010 1:13 am    Post subject: Reply with quote

Oh well, here is a shot with one, an Industar-61 LD @ f4.




PostPosted: Wed Dec 22, 2010 1:43 am    Post subject: Reply with quote

Yet another post in this forum about lens radioactivity? Rolling Eyes There are already so many here. We are lucky to have now several members who have performed tests using sensitive instrumentation which prove that radiation from lenses is in many cases less than that of the radon gas emitted by bare earth.

The only worrisome lenses are those that were used by government in nuclear research and energy facilities which may have been contaminated with radioactive dust -- these were sold through government surplus auctions.

Super, S-M-C, and SMC Takumars have some thorium in one or more of the coatings, iirc, used for refractive properties. Thoriated glass is used in some other lenses for refractive properties.

Some reactor waste products are used in inexpensive x-ray machines in US, probably elsewhere in the World. Some metal products made in China and elsewhere using recycled metals which do contain trace amounts of radioactive substances, such as silverware and jewelery, have been shown to have significant 'hot spots'.

If lenses are so radioactive where are reports of fogged film?

On my to do list is to attempt to photograph patterns of radioactivity using same principle as in Spinthariscope -- the patterns may perhaps be very beautiful!


PostPosted: Wed Dec 22, 2010 11:20 am    Post subject: Reply with quote

Some people simply took unexposed film in black plastic bags and place lenses on top for some time, then developed it.

A highly overrated topic, we have way too often discussed here.


PostPosted: Wed Dec 22, 2010 1:48 pm    Post subject: Reply with quote

kds315* wrote:
Some people simply took unexposed film in black plastic bags and place lenses on top for some time, then developed it.

A highly overrated topic, we have way too often discussed here.


Are there any examples? I have heard people tried that method without positive results because level was too low (or perhaps time too short). I am thinking a thin sheet of calcium fluoride may show collisions bright enough for a photo...


PostPosted: Fri Dec 24, 2010 12:40 pm    Post subject: Reply with quote

visualopsins wrote:

Super, S-M-C, and SMC Takumars have some thorium in one or more of the coatings, iirc, used for refractive properties. Thoriated glass is used in some other lenses for refractive properties.!!


The Thorium is in the element glass of the Takumars you mention too, not in the coatings!


PostPosted: Fri Dec 24, 2010 1:10 pm    Post subject: Reply with quote

visualopsins wrote:
kds315* wrote:
Some people simply took unexposed film in black plastic bags and place lenses on top for some time, then developed it.

A highly overrated topic, we have way too often discussed here.


Are there any examples? I have heard people tried that method without positive results because level was too low (or perhaps time too short). I am thinking a thin sheet of calcium fluoride may show collisions bright enough for a photo...


It takes several days of exposure!!