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fermy
Joined: 17 Feb 2012
Posts: 1312
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 Posted: Tue Jun 26, 2012 10:00 am Post subject: |
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| iangreenhalgh1 wrote: | It really staggers me that anyone worries about radiation from a lens.
Serious question, do the people who worry about radioactive lenses fly on aeroplanes for travel, holidays etc?
The dosage you receive from one flight is far greater than you would receive for years of exposure to a lens.
In future, perhaps it would be better to lock these threads early on, they really are pointless. |
What is really pointless is complaining about such threads. People here simply exchange information trying to understand what risks are there objectively. Repeating "there is no risk" one more time without providing any evidence does not contribute anything. If you have this issue figured out for yourself, simply don't participate.
It transpired that the dosage you receive flying is 1-10 milliSv/hr. The dosage you receive from Super Takumar in your pocket is also 1.65-10 milliSv/hr depending on how you carry it. That's exactly the same dosage. However, I'm flying about 20hrs/year. Now radioactive lenses tend to be really good; therefore they would spend a lot more than 20hrs/year in my pocket. So your statement is simply incorrect.
One cannot avoid flying without major inconvenience. On the other hand, one can easily avoid radioactive lenses as there are many interesting non-radioactive alternatives. Then the question arises if the benefits are worth the risk, however slight it is...
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tanheis
Joined: 05 Sep 2007
Posts: 492
Location: Finland
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| Posted: Tue Jun 26, 2012 1:10 pm Post subject: |
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| fermy wrote: | | iangreenhalgh1 wrote: | It really staggers me that anyone worries about radiation from a lens.
Serious question, do the people who worry about radioactive lenses fly on aeroplanes for travel, holidays etc?
The dosage you receive from one flight is far greater than you would receive for years of exposure to a lens.
In future, perhaps it would be better to lock these threads early on, they really are pointless. |
What is really pointless is complaining about such threads. People here simply exchange information trying to understand what risks are there objectively. Repeating "there is no risk" one more time without providing any evidence does not contribute anything. If you have this issue figured out for yourself, simply don't participate.
It transpired that the dosage you receive flying is 1-10 milliSv/hr. The dosage you receive from Super Takumar in your pocket is also 1.65-10 milliSv/hr depending on how you carry it. That's exactly the same dosage. However, I'm flying about 20hrs/year. Now radioactive lenses tend to be really good; therefore they would spend a lot more than 20hrs/year in my pocket. So your statement is simply incorrect.
One cannot avoid flying without major inconvenience. On the other hand, one can easily avoid radioactive lenses as there are many interesting non-radioactive alternatives. Then the question arises if the benefits are worth the risk, however slight it is... |
Well as I said 1-4 uSv / h is normal background radiation in some areas of earth like Kerala India.
I could move there without a problem even there are those places where is some radiation (natural)
Also I would not care about being flying a lot from work let's say few times a month. For me the radiation from those flights are nothing. It's more about do I like flying otherways.
Radiation like few uSv's / h is so small that total dose from that is not going to be big and remember it depends from the radiation will it even penetrate your skin as there are different alpha beta and gamma radiation.
- Alpha - these are fast moving helium atoms. They have high energy, typically in the MeV range, but due to their large mass, they
are stopped by just a few inches of air, or a piece of paper.
- Beta - these are fast moving electrons. They typically have energies in the range of a few hundred keV to several MeV. Since
electrons are might lighter than helium atoms, they are able to penetrate further, through several feet of air, or several millimeters
of plastic or less of very light metals.
- Gamma - these are photons, just like light, except of much higher energy, typically from several keV to several MeV. X-Rays and
gamma rays are really the same thing, the difference is how they were produced. Depending on their energy, they can be stopped
by a thin piece of aluminum foil, or they can penetrate several inches of lead.
I fly quite often on holidays and I have usually 7-10 hour flights one way + 2-4 shorter flights.
I have never thought radiation durring flight and still wont think it as a threat.
So many people work in airplanes and live normal lifes with that small radiation so I wont worry keeping the lens in closet and camera bag and sometimes connected to camera 
One 10 hour flight both ways is 20 hours.
If I shoot with the lens and touch the lens few seconds and take photos and totally touch the lens for 30min well... I can do that 40 times to get same dose than that flight.
Still I tink nobody thinks not going to Kerala because of radiation 
I have been there 1 month many times 24/7. No worries
_________________
EOS 5D mk II
Lenses: Nikkor 24mm 2.8, Pentacon 30 3.5, SMC Takumar 50 1.4, Nikon 50mm 1.4 AI-S & non-AI ones,Olympus OM Zuiko 28/2,Pentacon 50 1.8,Industar-50 50mm 3.5(silver & black) Tamron SP 90mm 2.5, Tokina 28-85 4, Tamron SP 35-80 2.8-3.8, Zeiss Tessar 45/2.8, Zeiss Planar 85/1.4,Nikon 105mm 1.8,Nikon 200/2 ED-IF AI-S,Seimar 135 2.8, Tamron SP 300mm 5.6, Tamron SP 60-300 3.8-5.4, Tamron SP 500mm 8.0 Mirror, Zenit Photosniper + Tair-3, Canon FD 800 5.6L - EOS converted |
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Aanything
Joined: 27 Aug 2011
Posts: 1029
Location: Milan
Expire: 2013-05-30
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| Posted: Tue Jun 26, 2012 1:53 pm Post subject: |
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I don't worry for the health damages radioactive lenses can deliver - I'm a smoker, and I'm quite overweight: I have more important threats to care about - but I think people who want to be worried about that has all the right to.
It doesn't really matter if someone gets more radiations doing other things he usually does: again, I'm a smoker, which exposes me to much higher cancer risk than if I weren't, but nevertheless i try to limit red meat in my diet (where "try" doesn't really mean I'm doing it).
I mean, it's not that if I do something that does harm, I have to do everything that does little less, nor that I can't worry about something because this something is less dangerous than things I do daily.
This is why I'm offering to take care of all the radioactive lenses that people here is wanting to get rid of. It's a dirty job, but someone has to do it. Just PM me, I'll give you the address.
Oh, i forgot to mention, the service is free for forum members 
_________________
C&C and editing of my pics are always welcome |
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SonicScot
Joined: 01 Dec 2011
Posts: 1414
Location: Scottish Highlands
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| Posted: Tue Jun 26, 2012 2:38 pm Post subject: |
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| Aanything wrote: | This is why I'm offering to take care of all the radioactive lenses that people here is wanting to get rid of. It's a dirty job, but someone has to do it. Just PM me, I'll give you the address.
Oh, i forgot to mention, the service is free for forum members |
You are a brave man and I salute you.
_________________
Gary
Currently active gear....
7D (Magic Lantern Alpha II)
3M-5CA 500/8
Tair 3 4.5/300-A
CZJ 180/2.8
CZJ 135/3.5
Vivitar Series 1 90/2.5 macro (Bokina)
Vivitar Series 1 70-210/3.5 (Kiron)
Jupiter-9 85/2
Helios 44-2 58/2
Nikon 50/1.2 Contax Zeiss Planar 50/1.7
Hartblei 45/3.5 Super-Rotator TS-PC
CZJ Flektogon 35/2.4
Samyang 8/3.5 fisheye
Flickr http://www.flickr.com/photos/gazsus/ Website http://garianphotography.co.uk/ |
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fermy
Joined: 17 Feb 2012
Posts: 1312
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| Posted: Tue Jun 26, 2012 3:26 pm Post subject: |
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| tanheis wrote: |
Radiation like few uSv's / h is so small that total dose from that is not going to be big and remember it depends from the radiation will it even penetrate your skin as there are different alpha beta and gamma radiation.
- Alpha - these are fast moving helium atoms. They have high energy, typically in the MeV range, but due to their large mass, they
are stopped by just a few inches of air, or a piece of paper.
- Beta - these are fast moving electrons. They typically have energies in the range of a few hundred keV to several MeV. Since
electrons are might lighter than helium atoms, they are able to penetrate further, through several feet of air, or several millimeters
of plastic or less of very light metals.
- Gamma - these are photons, just like light, except of much higher energy, typically from several keV to several MeV. X-Rays and
gamma rays are really the same thing, the difference is how they were produced. Depending on their energy, they can be stopped
by a thin piece of aluminum foil, or they can penetrate several inches of lead.
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I think what you have measured near the rear lens cap and especially on the sides is already filtered from alpha and low energy gamma radiation precisely because it should not penetrate the metal casing of Takumar. So 1.55 milliSv/hr likely consists of the particles that are able to penetrate your skin.
Overall, the numbers don't convince me that the associated risks are entirely trivial. Here's report on the dosages during Chernobyl disaster:
http://www.world-nuclear.org/info/chernobyl/inf07.html
| Report wrote: |
The next task was cleaning up the radioactivity at the site so that the remaining three reactors could be restarted, and the damaged reactor shielded more permanently. About 200,000 people ('liquidators') from all over the Soviet Union were involved in the recovery and clean-up during 1986 and 1987. They received high doses of radiation, averaging around 100 millisieverts. Some 20,000 of them received about 250 mSv and a few received 500 mSv. Later, the number of liquidators swelled to over 600,000 but most of these received only low radiation doses. The highest doses were received by about 1000 emergency workers and on-site personnel during the first day of the accident...
In the years following the accident, a further 220,000 people were resettled into less contaminated areas, and the initial 30 km radius exclusion zone (2800 km2) was modified and extended to cover 4300 square kilometres. This resettlement was due to application of a criterion of 350 mSv projected lifetime radiation dose, though in fact radiation in most of the affected area (apart from half a square kilometre) fell rapidly so that average doses were less than 50% above normal background of 2.5 mSv/yr.
According to the most up-to-date estimate of UNSCEAR, the average radiation dose due to the accident received by inhabitants of 'strict radiation control' areas (population 216,000) in the years 1986 to 2005 was 31 mSv (over the 20-year period), and in the 'contaminated' areas (population 6.4 million) it averaged 9 mSv, a minor increase over the dose due to background radiation over the same period (about 50 mSv)
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Now, one can easily reach 350mSV in one year by carrying a hot lens in a pocket just one hour per day. There are still hot debates on the exact health consequences of Chernobyl disaster, but to me it's clear that it makes no sense to carry a lens that can give in a year the dosage comparable with exposure of Chernobyl liquidators.
In reality, I think that the above Chernobyl estimates are too low (partly intentionally, partly due to difficulties in counting). Secondly, they assume the same exposure to the whole body, while the lens gives that level of exposure only to a very small spot. I don't think there is a reliable medical data on the health consequences of small point radiation doses, but logically it should be less damaging than the whole body exposure. So on the balance, I think that the risk is reasonably low (sorry Aanything, you are not getting my Nikkor-N 35/1.4), but it's definitely an issue worth investigating and far from open and shut case as some people trying to portray it.
_________________
Many lenses and some film bodies for sale here: http://forum.mflenses.com/canon-fd-minolta-md-c-mounts-m42-pentax-and-more-t50465.html |
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s58y
Joined: 05 Sep 2010
Posts: 127
Location: Eastern NY
Expire: 2013-09-10
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| Posted: Tue Jun 26, 2012 5:13 pm Post subject: |
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| fermy wrote: | | tanheis wrote: |
...
So 1.55 milliSv/hr likely consists of the particles that are able to penetrate your skin.
...
|
Now, one can easily reach 350mSV in one year by carrying a hot lens in a pocket just one hour per day. |
Wasn't the measured dosage from the lens 1.55 uSv/hr, not milli-Sv/hr? That's a lot more consistent with gamma readings I get of a few uSv/hr from various lenses near the front or rear glass.
To put the gamma radioactivity of the 50/1.4 S-M-C Tak in perspective, I get about 1.5x background approximately 1 foot from the lens, as measured by the gamma scintillator. This is 1.5 times my upstairs (inside) background. If I go outside (downstairs), the background goes up to about 1.4 times (and the whole body is exposed, too). If I were to lay down on the ground outside, the background goes up to around 1.8x the upstairs reading. If these readings are even close to accurate, using the 50/1.4 Takumar is not much different than lying down outside, where I live.
_________________
flickr photostream
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iangreenhalgh1
Joined: 18 Mar 2011
Posts: 9106
Expire: 2014-01-07
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| Posted: Tue Jun 26, 2012 5:43 pm Post subject: |
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| s58y wrote: | | fermy wrote: | | tanheis wrote: |
...
So 1.55 milliSv/hr likely consists of the particles that are able to penetrate your skin.
...
|
Now, one can easily reach 350mSV in one year by carrying a hot lens in a pocket just one hour per day. |
Wasn't the measured dosage from the lens 1.55 uSv/hr, not milli-Sv/hr? That's a lot more consistent with gamma readings I get of a few uSv/hr from various lenses near the front or rear glass.
To put the gamma radioactivity of the 50/1.4 S-M-C Tak in perspective, I get about 1.5x background approximately 1 foot from the lens, as measured by the gamma scintillator. This is 1.5 times my upstairs (inside) background. If I go outside (downstairs), the background goes up to about 1.4 times (and the whole body is exposed, too). If I were to lay down on the ground outside, the background goes up to around 1.8x the upstairs reading. If these readings are even close to accurate, using the 50/1.4 Takumar is not much different than lying down outside, where I live. |
Just to be on the safe side, don't use your Tak lying down! 
_________________
'The question I would really consider (especially if an amateur and on a budget) is whether or not anyone (including yourself, of course) can tell the difference in any situation for which you will use the lens...and if they can, why are they burying their noses in your prints hard enough to tell the difference instead of responding to the prints emotionally and thinking about what they might mean?' - 2F/2F on apug.org
Digital: Sony NEX-3, Samsung NX100, Canon EOS 450d
35mm SLR: Konica FT-1, Konica FC-1, Konica Autoreflex T, Carena SRH760, Exakta RTL1000, Canon EOS 10qd
35mm VF: Olympus Stylus, Konica C35, Konica A4, Konica MG, Konica MT-9, Ricoh FF-9, Ricoh AF-80
35mm RF: Zorki 6, Kiev II, Kiev IV, Contax IIIa, CZJ Werra III,
Medium format: Franka Rolfix, Mess Ikonta 524/16, Voigtlander Bessa with Skopar 3.5/105, Voigtlander Bessa with Voigtar 3.5/105, Kiev 6C, Century Graphic 23, Ensign Selfix 820, Kershaw 450
MF lenses: Schneider Angulon 6.5/68, Componon-S 5.6/100, C-Claron 4.5/135, Xenar 3.5/105, Mamiya C 2.8/45, Mamiya 2.8/80, CZJ Flektogon 4/50, Biometar 2.8/80, Zodiac 3.5/30, Tominon 4.5/135, Pullin Pulnar 2.8/100
Large Format: Ernemann HEAG Series VII version II 9x12 with Kodak Anastigmat 6.3/170
Konica Hexanons 4/21, 2.8/24, 3.5/28, 2.8/35, 1.8/40, 1.4/50, 1.7/50, 1.8/50, 3.2/135, 3.5/135, 3.5/200, 4.5/300, 3.5-4.5/35-70, 4-4.6/28-135, 3.5/35-70, UC 3.5/45-100, 4/70-150, 4/65-135, UC 4/80-200. Hexars 3.5/28, 3.5/135, Konishiroku 2.8/35
Carl Zeiss Jena Flektogon 2.8/35, Skoparex 3.4/35, Tessar 2.8/50, Sonnar 1.5/50, Biotar 2/58, Pancolar 1.8/50, Cardinar 4/100, Zeiss-Opton Biogon 2.8/35
Meyer/Pentacons 2.8/28, Primagon 4.5/35, Trioplan 2.9/50, 1.8/50, 2.4/50, Primotar 3.5/50, Primotar 3.5/135
Topcon RE Auto Topcors 1.8/58, 3.5/135, 5.6/200
Russians: OKC1-18-1 2.8/18, OKC1-28-1 2.8/28, Jupiter-12 2.8/35, Jupiter-8 2/50, Industar-50 3.5/50, Industar-26M 2.8/50, Industar-22 3.5/50, Zenitar M2S 2/50, Helios-44-2, Jupiter-9 2/85, Jupiter-11 4/135, Tair-3C 4.5/300
Tokina 3.5/17, Nikon Auto Nikkor-N 2.8/24, Nikon Micro-Nikkor-P 3.5/55, Ross Xpress 3.5/4in, Ross Xpress 4/5in, Ross Xpress 4.5/8.5in, Wollensak APO-Raptar 10/541
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tanheis
Joined: 05 Sep 2007
Posts: 492
Location: Finland
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| Posted: Tue Jun 26, 2012 9:45 pm Post subject: |
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| s58y wrote: | | fermy wrote: | | tanheis wrote: |
...
So 1.55 milliSv/hr likely consists of the particles that are able to penetrate your skin.
...
|
Now, one can easily reach 350mSV in one year by carrying a hot lens in a pocket just one hour per day. |
Wasn't the measured dosage from the lens 1.55 uSv/hr, not milli-Sv/hr? That's a lot more consistent with gamma readings I get of a few uSv/hr from various lenses near the front or rear glass.
To put the gamma radioactivity of the 50/1.4 S-M-C Tak in perspective, I get about 1.5x background approximately 1 foot from the lens, as measured by the gamma scintillator. This is 1.5 times my upstairs (inside) background. If I go outside (downstairs), the background goes up to about 1.4 times (and the whole body is exposed, too). If I were to lay down on the ground outside, the background goes up to around 1.8x the upstairs reading. If these readings are even close to accurate, using the 50/1.4 Takumar is not much different than lying down outside, where I live. |
Yes he is wrong about units. I measured uSv NOT mSv because milli Sv is 1000 times uSvh!
So now we where going in 1000 times wrong
As I also mentioned I measured uSv/h so it has nothing to do with mSv (milli Sv) if you wont calculate it again
Again if I would get 1.55 uSv / h 4 hours it's 6.2uSv dose then / day
2263 uSv dose / year which is just 2.26 mSv dose whole year which is not much. It's dose which normal worker get's from airplane / year but I never ever would hold it 4 hours every day so true radiation is so much less.
_________________
EOS 5D mk II
Lenses: Nikkor 24mm 2.8, Pentacon 30 3.5, SMC Takumar 50 1.4, Nikon 50mm 1.4 AI-S & non-AI ones,Olympus OM Zuiko 28/2,Pentacon 50 1.8,Industar-50 50mm 3.5(silver & black) Tamron SP 90mm 2.5, Tokina 28-85 4, Tamron SP 35-80 2.8-3.8, Zeiss Tessar 45/2.8, Zeiss Planar 85/1.4,Nikon 105mm 1.8,Nikon 200/2 ED-IF AI-S,Seimar 135 2.8, Tamron SP 300mm 5.6, Tamron SP 60-300 3.8-5.4, Tamron SP 500mm 8.0 Mirror, Zenit Photosniper + Tair-3, Canon FD 800 5.6L - EOS converted |
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fermy
Joined: 17 Feb 2012
Posts: 1312
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| Posted: Wed Jun 27, 2012 8:33 am Post subject: |
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| tanheis wrote: | | s58y wrote: | | fermy wrote: | | tanheis wrote: |
...
So 1.55 milliSv/hr likely consists of the particles that are able to penetrate your skin.
...
|
Now, one can easily reach 350mSV in one year by carrying a hot lens in a pocket just one hour per day. |
Wasn't the measured dosage from the lens 1.55 uSv/hr, not milli-Sv/hr? That's a lot more consistent with gamma readings I get of a few uSv/hr from various lenses near the front or rear glass.
|
Yes he is wrong about units. I measured uSv NOT mSv because milli Sv is 1000 times uSvh!
So now we where going in 1000 times wrong
|
Good! That looks 1000 times safer
_________________
Many lenses and some film bodies for sale here: http://forum.mflenses.com/canon-fd-minolta-md-c-mounts-m42-pentax-and-more-t50465.html |
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peterqd
Joined: 28 Feb 2007
Posts: 7599
Location: near High Wycombe, UK
Expire: 2014-01-04
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| Posted: Wed Jun 27, 2012 9:19 am Post subject: |
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| tanheis wrote: | | Yes he is wrong about units. |
Which proves that you can't trust anything you read on an internet forum!
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tanheis
Joined: 05 Sep 2007
Posts: 492
Location: Finland
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| Posted: Fri Jul 20, 2012 6:33 am Post subject: |
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Hello again
My newest addition to radioactive stuff is Fiestaware dinnerware plate from which I can also eat my breakfast
I measured the plate with my geiger counter and it gives 42 µSv / h.
That is around 4x the radiation of my Takumar and still this is a plate made for food
Plate looks like this: 
The orange/red glaze is made with uranium oxide.
Now all of you who have some these antique plates or other fiestaware stuff have stronger radioactive stuff than lenses.
I went to flea market and there I found everywhere radioactive uranium glass stuff like these (see the yellow / greenish color)
Many people here in Finland have these as those are antique stuff and have value.
I think many doesn't even know about their radioactivity. At least the sellers and customers didn't know when I found them with geiger counter
Those glass stuff give around 1/3 to 1/2 of the radiation compared to Takumar.
_________________
EOS 5D mk II
Lenses: Nikkor 24mm 2.8, Pentacon 30 3.5, SMC Takumar 50 1.4, Nikon 50mm 1.4 AI-S & non-AI ones,Olympus OM Zuiko 28/2,Pentacon 50 1.8,Industar-50 50mm 3.5(silver & black) Tamron SP 90mm 2.5, Tokina 28-85 4, Tamron SP 35-80 2.8-3.8, Zeiss Tessar 45/2.8, Zeiss Planar 85/1.4,Nikon 105mm 1.8,Nikon 200/2 ED-IF AI-S,Seimar 135 2.8, Tamron SP 300mm 5.6, Tamron SP 60-300 3.8-5.4, Tamron SP 500mm 8.0 Mirror, Zenit Photosniper + Tair-3, Canon FD 800 5.6L - EOS converted |
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dnas
Joined: 14 Nov 2008
Posts: 302
Location: Japan
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| Posted: Mon Dec 03, 2012 12:00 am Post subject: |
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I have recently had access to a radiation dose meter.
I live in Japan, and some visitors were worried about radiation dose in one area of Japan, where they would be working. This area is about 80km from the Fukushima nuclear reactors that suffered meltdown in March 2011, following the magnitude 9 earthquake and tsunami. I was located about 250km away at the time, in Tokyo.
Global average - 0.27 micro Sv/h
The radiation dose was measured by myself as follows:
Tokyo, Japan - between 0.07 - 0.12 micro Sv/h
Seoul, S.Korea - between 0.14 - 0.17 micro Sv/h
(Not measured by myself, but in Fukushima Prefecture, Japan, 50km north of nuclear reactors - between 0.67 - 0.75 micro Sv/h. )
In aircraft between Tokyo - Seoul at 39,000 feet (11,800m)
- between 1.55 - 1.70 micro Sv/h
Pentax Takumar SMC 50mm F1.4
Front of lens:
- between 0.25 - 0.65 micro Sv/h (I will recheck these figures)
Rear of lens:
- between 9.80 - 12.5 micro Sv/h
Pentax Super Takumar 50mm F1.4
Front of lens:
- between 0.xx - 0.xx micro Sv/h (I will recheck these figures)
Rear of lens:
- between 7.50 - 10.0 micro Sv/h |
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Nikonshooter
Joined: 12 Nov 2012
Posts: 165
Location: Gunsan, Korea
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| Posted: Mon Dec 03, 2012 6:56 am Post subject: |
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| dnas wrote: | I have recently had access to a radiation dose meter.
I live in Japan, and some visitors were worried about radiation dose in one area of Japan, where they would be working. This area is about 80km from the Fukushima nuclear reactors that suffered meltdown in March 2011, following the magnitude 9 earthquake and tsunami. I was located about 250km away at the time, in Tokyo.
Global average - 0.27 micro Sv/h
The radiation dose was measured by myself as follows:
Tokyo, Japan - between 0.07 - 0.12 micro Sv/h
Seoul, S.Korea - between 0.14 - 0.17 micro Sv/h
(Not measured by myself, but in Fukushima Prefecture, Japan, 50km north of nuclear reactors - between 0.67 - 0.75 micro Sv/h. )
In aircraft between Tokyo - Seoul at 39,000 feet (11,800m)
- between 1.55 - 1.70 micro Sv/h
Pentax Takumar SMC 50mm F1.4
Front of lens:
- between 0.25 - 0.65 micro Sv/h (I will recheck these figures)
Rear of lens:
- between 9.80 - 12.5 micro Sv/h
Pentax Super Takumar 50mm F1.4
Front of lens:
- between 0.xx - 0.xx micro Sv/h (I will recheck these figures)
Rear of lens:
- between 7.50 - 10.0 micro Sv/h |
I was living in Japan when the quake hit. I helped move tons of Cargo and relief supplies to aid the Japanese.
Wow that's more than normal! I think I'm selling my lens, but not until I see if the quality is worth it.
_________________
D7000
Nikon 50mm E F1.8
Vivitar 70-210mm F3.5 x4
Rokinon 28mm F2.8
Nikon 35mm E F2.5
Jupiter 9 (1954)
SMC Takumar 28mm 3.5
Super Takumar 200mm 3.5
SMC TAKUMAR 135MM 2.5 |
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dnas
Joined: 14 Nov 2008
Posts: 302
Location: Japan
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| Posted: Mon Dec 03, 2012 7:14 am Post subject: |
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If you pressed the back of the lens hard against your skin for one hour a day for 3 months, you would end up with about twice the dose you would normally get in year.....
In other words, nothing to worry about!!!! |
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elliott
Joined: 16 May 2011
Posts: 120
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| Posted: Mon Dec 03, 2012 7:26 am Post subject: |
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| dnas wrote: | | If you pressed the back of the lens hard against your skin for one hour a day for 3 months, you would end up with about twice the dose you would normally get in year..... |
Keep in mind that is the lens directly against you, not mounted on a camera, a camera body will block nearly all of the radiation.
Though, if you happen to have a radioactive Takumar 35mm f2, they are extremely dangerous and I am qualified to dispose of both SMC and Super Takumar varieties for a reasonable fee. |
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