View previous topic :: View next topic |
Author |
Message |
lauge
Joined: 14 Jun 2008 Posts: 101 Location: Copenhagen, Denmark
Expire: 2013-05-30
|
Posted: Thu Aug 07, 2008 2:29 pm Post subject: Radioactive lenses |
|
|
lauge wrote:
This is a follow up on a previous post about Industar 61L/Z and radioactivity
I leant my S-M-C Takumar 50/1.4 and Industar 61L/Z to a specialist in radioactive materials and I got some interesting answers.
The Takumar did indeed contain Thorium but the radiation was only measurable very close to the lens so it's really not that radioactive. Naturally occurring Thorium (232) has a half-life of 1.405E10 years. The Industar on the other hand did not emit any radiation and the explanation for that is that most likely made of naturally occuring Lanthanium. La-139 is stable and is 99.910% of naturally occurring Lanthanium. La-138 has a half-life of 1.02E11 years and is 0.090% of naturally occurring Lanthanium.
Naturally occurring Thorium and Lanthanium has a large half-life so it is most unlikely that decaying will have any impact on the lens. So the conclusion must be that it's pretty safe to buy lenses containing Thorium and Lanthanium. _________________ M42:
S-M-C Takumar: 3.5/28 1.4/50 2.8/105
USSR: Industar 61L/Z
CZJ: Flektogon 2.4/35
MD:
Rokkor: 35-70/3.5
Kiron: 2.8/105 Macro
OM:
Zuiko: 50/1.8 75-150/4
Sigma: 24/2.8
Cameras:
Asahi Spotmatic F (looking for a sample with working light meter)
Olympus OM-1
Zeiss Ikon Contaflex IV
NEX 7 Sony A55 Konica Minolta Dynax 5D Minolta Dynax 7 Minolta AF 7000 |
|
Back to top |
|
|
zewrak
Joined: 12 Apr 2008 Posts: 1212
|
Posted: Thu Aug 07, 2008 2:32 pm Post subject: Re: Radioactive lenses |
|
|
zewrak wrote:
Damnit! And here I am saving up lenses for a bomb. Your telling me its futile?
PS. Hello FRA. _________________ My homepage, all manual shots |
|
Back to top |
|
|
Nesster
Joined: 24 Apr 2008 Posts: 5883 Location: NJ, USA
Expire: 2014-02-20
|
Posted: Thu Aug 07, 2008 3:28 pm Post subject: |
|
|
Nesster wrote:
Actually, if you use them as projection lenses you get a Death Ray Machine. _________________ -Jussi
Camera photos
Print Photographica
|
|
Back to top |
|
|
ChrisLilley
Joined: 01 Jan 2008 Posts: 1767 Location: Nice, France
|
Posted: Thu Aug 07, 2008 3:39 pm Post subject: |
|
|
ChrisLilley wrote:
Thanks, that was informative. _________________ Camera (ˈkæ mə rə), n. Device for taking pictures in bright light
There are 10 kinds of people in the world: those who understand binary, and those who don’t. Key: Ai-P, Ai, Ai'ed, AiS
Camera: Nikon D90, D40, DK-21M eyepiece, ML-3 remote MF lenses: Nikkor 20mm f/4 K, AI'ed | N.K. Nikkor-N 24mm f/2.8 | Nikkor-N.C 24mm f/2.8 | Nikkor 28mm f/2.8 AiS late model | Арсенал (Arsenal) Мир-24Н (Mir-24N) 35mm f/2 | Cosina Voigtländer Ultron SL II 40mm f/2.0 | Micro-Nikkor 55mm f/2.8 AiS | Zoom-Nikkor 80-200 f/4.5 Ai | ЛЗОС (LZOS) Юпитер-9 (Jupiter-9) 85mm f/2 | Cosina Voigtländer APO-Lanthar 90mm f/3.5 SL | Nikkor-P 105mm f/2.5 pre-Ai, Ai'ed | Micro-Nikkor 105mm f/4 | Schneider Kreuznach Componon 105mm f/5.6 | Nikkor 135mm f/2.8, Ai'ed 1976 model | Nikkor 180mm f/2.8 ED AiS | Арсенал (Arsenal) ТЕЛЕАР-Н (Telear-n) 200mm f/3.5 | Nikkor 300 mm f/4.5 Ai (full equipment list) |
|
Back to top |
|
|
no-X
Joined: 19 Jul 2008 Posts: 2495 Location: Budejky, Czech Republic
|
Posted: Thu Aug 07, 2008 4:17 pm Post subject: |
|
|
no-X wrote:
Takumars use thoriated glass only for the rear element. Radioactivity near front elment is very low, but near rear part it's higher than on famous aero-ektars.
at least these Asahi lenses use thorium:
- Super / Super Multi-Coated Takumar 35mm / 1:2 (later version with 49mm filter thread)
- Super / Super Multi-Coated / SMC Takumar 50mm / 1:1.4 (later Super version and all SMC)
- Super / Super Multi-Coated Macro Takumar 50mm / 1:4
- Super / Super Multi-Coated Takumar 55mm / 1:2
tomioka lenses:
- Yashinon-DX 28mm / 1:2.8
- Yashinon 55mm / 1:1.2
- Yashinon-DS 50mm / 1:1.4
- Yashinon-DS 50mm / 1:1.7
- Yashinon DS-M 50mm / 1:1.4
- Yashinon DS-M 50mm / 1:1.7
- Yashinon DS-M 55mm / 1:1.2
earlier versions get yellowish cast, newer (DS-M) use other optical glue, which is stable doesn't turn yellow
There are 4 ways to remove the color cast:
1. sun (attention, curtains are highly flammable)
2. UV lamp + tinfoil (not good for eyes, best closed in case)
3. optical glue exchange (quite expensive)
4. so-called Ayling's method
I use 11W UV tube and 4 weeks is enough for removal of >95% color cast. Left: before, each next: 1 week under UV tube:
It should also eliminate spores of fungus.
There was a story about a photographer, who had some problems in a nuclear power plant, because the safety equipment analysed his camera as contaminated.
I've also read somewhere, that one day of photography (using radioactive lens) means same level of irradiation as one transatlantic flight.
here are some interesting links:
http://yashica.org/254-2-Lens-radioactivity-measurements.html
http://photo.net/large-format-photography-forum/005obo
http://www.orau.org/PTP/collection/consumer%20products/cameralens.htm _________________ (almost) complete list of Helios lenses |
|
Back to top |
|
|
Prometheus
Joined: 27 Feb 2008 Posts: 878 Location: Garphyttan, Sweden
|
Posted: Thu Aug 07, 2008 4:52 pm Post subject: |
|
|
Prometheus wrote:
Mine seems to be ok (?)
Yashinon-DX 50mm 1:1.7 84nSv/h
Yashica ML 50mm 1:2 81nSv/h _________________ Retrocamera.net |
|
Back to top |
|
|
Schnauzer
Joined: 09 Apr 2008 Posts: 2155 Location: Maine, USA
Expire: 2012-03-08
|
Posted: Thu Aug 07, 2008 6:01 pm Post subject: |
|
|
Schnauzer wrote:
I don't buy these lenses because I heard that if you carry any of them in your front pockets you will become sterile. _________________ Ron |
|
Back to top |
|
|
no-X
Joined: 19 Jul 2008 Posts: 2495 Location: Budejky, Czech Republic
|
Posted: Thu Aug 07, 2008 6:24 pm Post subject: |
|
|
no-X wrote:
TheFlyingCamera wrote: |
...don't sleep with the lens between your thighs or you'll have funny-looking children. |
_________________ (almost) complete list of Helios lenses |
|
Back to top |
|
|
koji
Joined: 21 Jul 2008 Posts: 2106 Location: Hiroshima, Japan
Expire: 2012-12-27
|
Posted: Thu Aug 07, 2008 7:26 pm Post subject: |
|
|
koji wrote:
No it is NOT kidding. see >
http://homepage3.nifty.com/ohbehello/kizai_shitsu_page_lens_housyasen_list.htm
http://homepage3.nifty.com/ohbehello/the_fl_lens_waku2/fl_lens_housyasen_sokutei.htm
Natural background radiation is normally 0.020 - 0.045 micro Sv / H,
so some of them are pretty dangerous to your possible descendant(s). _________________ Our Home Page has 18,200 photos in 575 directories today.
Lenses: https://www.pbase.com/kkawakami/top_level_my_lenses |
|
Back to top |
|
|
no-X
Joined: 19 Jul 2008 Posts: 2495 Location: Budejky, Czech Republic
|
Posted: Thu Aug 07, 2008 8:07 pm Post subject: |
|
|
no-X wrote:
According to US Code of Federal Regulations there are no restrictions in connection with lenses that contain less than 30 percent by weight of thorium.
Typical thoriated glass elements contains 2-4x time lower concentration of thorium. It should be safe for normal usage, but it's not reccomended to keep thoriated lens under your bed or to stock them (in larger quantities) in your bedroom, or just behind wall which is near upon your bed. _________________ (almost) complete list of Helios lenses |
|
Back to top |
|
|
lauge
Joined: 14 Jun 2008 Posts: 101 Location: Copenhagen, Denmark
Expire: 2013-05-30
|
Posted: Thu Aug 07, 2008 8:12 pm Post subject: |
|
|
lauge wrote:
Thorium is an alpha emitter but has some gamma radiation which is the worst kind of external radiation. As also mentioned else where in this forum a fluorescent watch is also radioactive which only harmed the workers painting this material on. I guess it's the same reason that they don't make lenses with thorium element in them since the radioactive source is too vague to do any harm.
I think you will need an M42 to "scrutom" adapter and mount it a fair amount of time to achieve funny looking children. _________________ M42:
S-M-C Takumar: 3.5/28 1.4/50 2.8/105
USSR: Industar 61L/Z
CZJ: Flektogon 2.4/35
MD:
Rokkor: 35-70/3.5
Kiron: 2.8/105 Macro
OM:
Zuiko: 50/1.8 75-150/4
Sigma: 24/2.8
Cameras:
Asahi Spotmatic F (looking for a sample with working light meter)
Olympus OM-1
Zeiss Ikon Contaflex IV
NEX 7 Sony A55 Konica Minolta Dynax 5D Minolta Dynax 7 Minolta AF 7000 |
|
Back to top |
|
|
no-X
Joined: 19 Jul 2008 Posts: 2495 Location: Budejky, Czech Republic
|
Posted: Thu Aug 07, 2008 8:33 pm Post subject: |
|
|
no-X wrote:
Michael S. Briggs. wrote: |
The statement that Thorium and its daughters decay via alpha and beta emissions is correct, but neglects the fact that many of the daughter isotopes are created in excited states. These excited isotopes quickly transition to their ground states by the emission of gamma-rays. The atomic electrons also readjust their states by the emission of X-rays. Blocking the X-rays and especially the gamma-rays require much more shielding than blocking alpha and beta particles. |
http://home.earthlink.net/~michaelbriggs/aeroektar/aeroektar.html _________________ (almost) complete list of Helios lenses |
|
Back to top |
|
|
Orio
Joined: 24 Feb 2007 Posts: 29545 Location: West Emilia
Expire: 2012-12-04
|
Posted: Thu Aug 07, 2008 11:38 pm Post subject: |
|
|
Orio wrote:
In other words: should I sell my SMC Takumar 1.4/50?
Is it safe to take it with me for a holiday, so that it will stay most of the time either at my neck on the camera, or next to my waist inside the bag? _________________ Orio, Administrator
T*
NE CEDE MALIS AUDENTIOR ITO
Ferrania film is reborn! http://www.filmferrania.it/
Support the Ornano film chemicals company and help them survive!
http://forum.mflenses.com/ornano-chemical-products-t55525.html |
|
Back to top |
|
|
vilva
Joined: 04 Mar 2007 Posts: 785 Location: Porvoo/Borgå, Finland
Expire: 2015-05-27
|
Posted: Fri Aug 08, 2008 2:52 am Post subject: |
|
|
vilva wrote:
Orio wrote: |
In other words: should I sell my SMC Takumar 1.4/50?
Is it safe to take it with me for a holiday, so that it will stay most of the time either at my neck on the camera, or next to my waist inside the bag? |
This seems to be an ever repeating theme, and once again, a concise explanation can be found at http://www.hps.org/publicinformation/ate/q1356.html.
I wouldn't worry, especially as the received dose will very quickly diminish with distance: at ten times the distance, the dose on a given area will be 1/100.
Veijo _________________ Mainly Schneider-Kreuznach Radionar (1938), VPK Meniscus Achromat (1915), TTH Cooke Anastigmat (1917), TTH Cooke Aviar (1937), Goerz Dopp-Anastigmat III Dagor (1912), Voigländer Heliar (1928) or Aldis Uno Series III (1903 design) mounted on EOS 5D or EOS 350D |
|
Back to top |
|
|
zewrak
Joined: 12 Apr 2008 Posts: 1212
|
Posted: Fri Aug 08, 2008 6:32 am Post subject: |
|
|
zewrak wrote:
Orio wrote: |
In other words: should I sell my SMC Takumar 1.4/50?
Is it safe to take it with me for a holiday, so that it will stay most of the time either at my neck on the camera, or next to my waist inside the bag? |
You have to remember Orio, without radiation niether the Hulk or Spiderman would have been the superheros they are.
I would be more worried of mobile and wireless phones, especially the later. _________________ My homepage, all manual shots |
|
Back to top |
|
|
lauge
Joined: 14 Jun 2008 Posts: 101 Location: Copenhagen, Denmark
Expire: 2013-05-30
|
Posted: Fri Aug 08, 2008 7:08 am Post subject: |
|
|
lauge wrote:
Orio wrote: |
In other words: should I sell my SMC Takumar 1.4/50?
Is it safe to take it with me for a holiday, so that it will stay most of the time either at my neck on the camera, or next to my waist inside the bag? |
The reply I got from the specialist(s) was that the radiation was only measurable very close to the lens and that such small amount of radiation wouldn't harm. It's more likely that it's not used today to protect the assembly workers, or better materials has been discovered?
Both specialist should be a very reliable source since it's their job to warn about radioactive hazards (is that what it's called?) _________________ M42:
S-M-C Takumar: 3.5/28 1.4/50 2.8/105
USSR: Industar 61L/Z
CZJ: Flektogon 2.4/35
MD:
Rokkor: 35-70/3.5
Kiron: 2.8/105 Macro
OM:
Zuiko: 50/1.8 75-150/4
Sigma: 24/2.8
Cameras:
Asahi Spotmatic F (looking for a sample with working light meter)
Olympus OM-1
Zeiss Ikon Contaflex IV
NEX 7 Sony A55 Konica Minolta Dynax 5D Minolta Dynax 7 Minolta AF 7000 |
|
Back to top |
|
|
Prometheus
Joined: 27 Feb 2008 Posts: 878 Location: Garphyttan, Sweden
|
Posted: Fri Aug 08, 2008 9:16 am Post subject: |
|
|
Prometheus wrote:
lauge wrote: |
The reply I got from the specialist(s) was that the radiation was only measurable very close to the lens and that such small amount of radiation wouldn't harm. It's more likely that it's not used today to protect the assembly workers, or better materials has been discovered?
Both specialist should be a very reliable source since it's their job to warn about radioactive hazards (is that what it's called?) |
Thanks for that clarification, now I don't have to worry that my one-year old daughter spend to much time near the cameras. _________________ Retrocamera.net |
|
Back to top |
|
|
Razster
Joined: 05 Feb 2008 Posts: 101
|
Posted: Fri Aug 08, 2008 7:51 pm Post subject: |
|
|
Razster wrote:
If you're going to get rid of your Pentax lenses send them my way |
|
Back to top |
|
|
LucisPictor
Joined: 26 Feb 2007 Posts: 17633 Location: Oberhessen, Germany / Maidstone ('95-'96)
Expire: 2013-12-03
|
Posted: Tue Aug 19, 2008 7:14 pm Post subject: |
|
|
LucisPictor wrote:
zewrak wrote: |
I would be more worried of mobile and wireless phones, especially the later. |
Very true! _________________ Personal forum activity on pause every now and again (due to job obligations)!
Carsten, former Moderator
Things ON SALE
Carsten = "KAPCTEH" = "Karusutenu" | T-shirt?.........................My photos from Emilia: http://www.schouler.net/emilia/emilia2011.html
My gear: http://retrocameracs.wordpress.com/ausrustung/
Old list: http://forum.mflenses.com/viewtopic.php?t=65 (Not up-to-date, sorry!) | http://www.lucispictor.de | http://www.alensaweek.wordpress.com |
http://www.retrocamera.de |
|
Back to top |
|
|
BobDodds
Joined: 13 Nov 2007 Posts: 87
|
Posted: Wed Oct 08, 2008 6:38 am Post subject: |
|
|
BobDodds wrote:
The Canon FL 58mm f1.2 is thoriated. Very nice but no reasonable way to convert to dslr.
Zuiko 55mm, not 50mm, f1.2 is thoriated. 55mm came first, and thorium couldn't make it sharp. 50mm is flat field sharp like a macro lens, 55mm might make a nice portrait lens like helios 40-2 but it's a lemon in the Zuiko line.
There you have it. Zuiko 55mm f1.2 thoriated does not always produce the right kind of funny babies, like X-M3n. |
|
Back to top |
|
|
Orio
Joined: 24 Feb 2007 Posts: 29545 Location: West Emilia
Expire: 2012-12-04
|
Posted: Wed Oct 08, 2008 7:29 am Post subject: |
|
|
Orio wrote:
Prometheus wrote: |
Thanks for that clarification, now I don't have to worry that my one-year old daughter spend to much time near the cameras. |
Or maybe you have to worry, but for your lenses _________________ Orio, Administrator
T*
NE CEDE MALIS AUDENTIOR ITO
Ferrania film is reborn! http://www.filmferrania.it/
Support the Ornano film chemicals company and help them survive!
http://forum.mflenses.com/ornano-chemical-products-t55525.html |
|
Back to top |
|
|
Wormhandler
Joined: 19 May 2008 Posts: 106 Location: Sweden
|
Posted: Wed Oct 08, 2008 9:10 am Post subject: |
|
|
Wormhandler wrote:
Zewrak wrote:
"PS. Hello FRA."
As a fellow Swede that made me laugh real good.
/Jan |
|
Back to top |
|
|
doomed-forever
Joined: 09 Aug 2014 Posts: 239
|
Posted: Wed Apr 15, 2015 5:12 pm Post subject: |
|
|
doomed-forever wrote:
Even the Yashica ML 50/2 is leaking some neglible Radiation? Well, i don't own the lens, but the 50/1.7 ML, 50/1.4 and many others...and guess what, the lenses are into a Box on my Bed, no kidding - because elsewhere i haven't found space for them...huh... |
|
Back to top |
|
|
stevemark
Joined: 29 Apr 2011 Posts: 3751 Location: Switzerland
|
Posted: Mon Apr 20, 2015 10:29 am Post subject: |
|
|
stevemark wrote:
doomed-forever wrote: |
Even the Yashica ML 50/2 is leaking some neglible Radiation? Well, i don't own the lens, but the 50/1.7 ML, 50/1.4 and many others...and guess what, the lenses are into a Box on my Bed, no kidding - because elsewhere i haven't found space for them...huh... |
That might not be the best idea - i keep my three radioactive lenses (three versions of the Minolta MC 2.5/28mm) a least 3 m away from where i work / sleep.
Steve _________________ www.artaphot.ch |
|
Back to top |
|
|
doomed-forever
Joined: 09 Aug 2014 Posts: 239
|
Posted: Mon Apr 20, 2015 5:40 pm Post subject: |
|
|
doomed-forever wrote:
I know...i'd move them to my night cupboard. |
|
Back to top |
|
|
|
|
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum
|