Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
08-06-2012, 11:15 AM   #1
Senior Member




Join Date: Jul 2012
Posts: 121
Radioactive lens problem

Hi,

So I'm planning to buy a radioactive lens. I know it sounds crazy.. but it's a fantastic lens in great condition, it's just radioactive. The last thing I want is for my family to be harmed from the radiation of the lens. Do you think lead foil will be enough to protect from radiation? Or do I need something thicker?

Thanks,
Nicole

08-06-2012, 11:18 AM   #2
Senior Member
simbon4o's Avatar

Join Date: Jan 2011
Photos: Gallery | Albums
Posts: 258
I don't think that it is dangerous . Most of the sources says that it is less radioactive then average mobile phone. So it must not be a huge problem.
08-06-2012, 11:20 AM   #3
Inactive Account




Join Date: Dec 2008
Location: North Carolina
Photos: Albums
Posts: 1,720
Less than 1 inch of air is more than enough to "protect" from the super low radiation given off by thoriated lenses. Now protecting yourself from the many other more powerful radiation sources that you likely encounter on a daily basis is more difficult.

If these lenses gave off any significant radiation they would have fogged the film in the cameras.
08-06-2012, 11:20 AM   #4
Veteran Member
Frogfish's Avatar

Join Date: Dec 2009
Location: Shanghai
Posts: 4,490
I assume you are talking about some of the USSR lenses ? As far as I'm aware there was never any danger from them - just over-reaction from the West. However to be on the safe side wear a tin-foil helmet when using the lens

08-06-2012, 11:24 AM   #5
Pentaxian
mikeSF's Avatar

Join Date: Jan 2009
Location: East Bay Area, CA
Photos: Gallery
Posts: 5,541
dont worry and have fun with it!
08-06-2012, 11:26 AM   #6
Inactive Account




Join Date: Dec 2008
Location: North Carolina
Photos: Albums
Posts: 1,720
QuoteOriginally posted by Frogfish Quote
I assume you are talking about some of the USSR lenses ? As far as I'm aware there was never any danger from them - just over-reaction from the West. However to be on the safe side wear a tin-foil helmet when using the lens
Soviet lenses are not radioactive, it is most common in Japanese and German glass, thoriated glass was far too expensive and complex for the Soviets.
08-06-2012, 11:27 AM   #7
Site Supporter
Deimos's Avatar

Join Date: Oct 2010
Location: Kingdom of Wonder
Posts: 1,707
avoid grinding up the rear element and serving it with dinner and you should be fine
08-06-2012, 11:30 AM   #8
Senior Member




Join Date: Jul 2012
Posts: 121
Original Poster
QuoteOriginally posted by elliott Quote
Soviet lenses are not radioactive, it is most common in Japanese and German glass, thoriated glass was far too expensive and complex for the Soviets.
Yes I am talking about japanese lenses, I heard that they were quite expensive to make and each copy made the company loose money.

QuoteOriginally posted by elliott Quote
Less than 1 inch of air is more than enough to "protect" from the super low radiation given off by thoriated lenses. Now protecting yourself from the many other more powerful radiation sources that you likely encounter on a daily basis is more difficult.
Okay, so you think that they won't be harmful at all? Or should I still protect myself from the lens when I'm not using it?

08-06-2012, 11:31 AM   #9
Veteran Member
Frogfish's Avatar

Join Date: Dec 2009
Location: Shanghai
Posts: 4,490
QuoteOriginally posted by elliott Quote
Soviet lenses are not radioactive, it is most common in Japanese and German glass, thoriated glass was far too expensive and complex for the Soviets.
Oops my mistake - I thought the Industar lenses were supposed to have minute quantities of radioactive material. Now if you are buying any Russian lenses on EBay that may have came from Chernobyl ......
08-06-2012, 11:38 AM   #10
Senior Member




Join Date: Jul 2012
Posts: 121
Original Poster
how much radiation does this lens "let out" compared to a fire alarm or mobile phone? If it's less, then I will buy it. I don't know if I would buy the lens if it let out more radiation as I will be putting the lens pretty close to my face..
08-06-2012, 11:38 AM   #11
Site Supporter
boriscleto's Avatar

Join Date: Dec 2009
Location: Liverpool, NY
Photos: Gallery
Posts: 12,310
QuoteOriginally posted by iNicole Quote
Yes I am talking about japanese lenses, I heard that they were quite expensive to make and each copy made the company loose money.
As ahi introduced the Thoriated Super Takumar 50/1.4 (7-element) because it was less expensive than the non-Thoriated Super Takumar 50/1.4 (8-element).

QuoteQuote:
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
Thoriated Camera Lens (ca. 1970s)
08-06-2012, 11:38 AM   #12
Pentaxian




Join Date: Oct 2011
Location: Savannah, GA
Posts: 4,989
Sounds like you are talking about some of the old Takumars. You don't have to worry about protecting yourself from it. You may have to give the glass a UV treatment to get rid of yellowing though...
08-06-2012, 11:39 AM   #13
Senior Member




Join Date: Jul 2012
Posts: 121
Original Poster
QuoteOriginally posted by boriscleto Quote
As ahi introduced the Thoriated Super Takumar 50/1.4 (7-element) because it was less expensive than the non-Thoriated Super Takumar 50/1.4 (8-element).
the 8-element version is not radioactive?
08-06-2012, 11:41 AM   #14
Site Supporter
boriscleto's Avatar

Join Date: Dec 2009
Location: Liverpool, NY
Photos: Gallery
Posts: 12,310
QuoteOriginally posted by iNicole Quote
the 8-element version is not radioactive?
That is correct. The 8-element was only produced in 1965 and was not radioactive.
08-06-2012, 11:45 AM   #15
Inactive Account




Join Date: Dec 2008
Location: North Carolina
Photos: Albums
Posts: 1,720
QuoteOriginally posted by Frogfish Quote
Oops my mistake - I thought the Industar lenses were supposed to have minute quantities of radioactive material. Now if you are buying any Russian lenses on EBay that may have came from Chernobyl ......
I think there is one Industar that uses lanthanum instead of thorium, but it is very uncommon to find, unlike the ubiquitous Super Takumar 50mm f1.4.

QuoteOriginally posted by iNicole Quote
Okay, so you think that they won't be harmful at all? Or should I still protect myself from the lens when I'm not using it?
I've never treated my Super Takumar any different from my other lenses, other than using UV light to clear up the yellowing caused by the decay of the thorium. It is such a low dose of radiation that it would take a very, very long time to add up to anything that could do any measurable damage to the human body, I'm talking about 24/7 direct exposure for years.

It is pointless to compare it to a mobile phone because it is a totally different thing, a mobile phone emits radio waves, not alpha, beta or gamma rays, it is not ionizing radiation. A smoke alarm is probably more dangerous if kept at a similar distance, but you're never really that close to one for any extended period of time.

Last edited by elliott; 08-06-2012 at 11:53 AM.
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
k-mount, lens, pentax lens, radiation, slr lens
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
How radioactive are the Super Takumars? Iivan Pentax Film SLR Discussion 84 07-31-2014 05:37 PM
Is this a front focusing camera problem or lens problem? Lens tests Metalwizards Pentax K-r 15 03-06-2011 01:24 AM
Takumar 50mm f1.4 Radioactive? Abstract Pentax SLR Lens Discussion 45 10-27-2010 09:38 AM
Helios 44-2 old version lens - radioactive? xpress Pentax SLR Lens Discussion 2 11-14-2009 10:32 AM
So who has a Radioactive Lens? konraDarnok Pentax SLR Lens Discussion 24 10-02-2009 02:37 PM



All times are GMT -7. The time now is 08:38 AM. | See also: NikonForums.com, part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top