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Archive 2010Beware Radioactive Lenses
p.3 #1Beware Radioactive Lenses
UV is damaging to DNA.... there's a reason our tissue culture hoods have short wavelength UV germicidal lamps... cross links the DNA 
... great for getting rid of contaminating plasmid DNA... not so good for you (also the main reason for wearing your sunblock at the beach... or just staying in the shade during peak hours)....
... great for getting rid of contaminating plasmid DNA... not so good for you (also the main reason for wearing your sunblock at the beach... or just staying in the shade during peak hours)....Dec 17, 2010 at 03:36 PM
p.3 #2Beware Radioactive Lenses
something else to worry about! My uncle was a nuclear physicist, and my aunt wouldn't allow a microwave cooker in the house - never quite worked out why but I figured she knew something I didn't!Dec 17, 2010 at 03:38 PM
p.3 #3Beware Radioactive Lenses
My Yashica 28/2.8 is rated at 210nSv/h. The average dose rate on Swiss territory outdoors is 147 nSv/h. I'm not concerned.
Wider and faster lenses are more likely to have higher radiation. If you are concerned and want to know if it's radioactive, place the lens on a piece of unexposed B&W film (Faster ASA / ISO should work better) in a dark closet for 24 hours. Have the sheet of film developed. If you see streaking or other strange marks where the lens was, you have a radioactive lens.
If you are worried about the radiation, you should remove all of your smoke detectors while you are at it because they emit radiation as well.
In truth, alpha particles are stopped by just about anything and everything, including a few inches of air. Unless you are holding the back of one of these lenses directly up to your eye, your camera and hands will probably be blocking any harmful radiation.
While microwave ovens use non-ionizing radiation, high frequency radio waves are very harmful to soft tissue. I'd be more worried about watching my food cook in one than being worried about the dose of alpha and beta particles that may be hitting my face from my lens.
Edited on Dec 17, 2010 at 04:36 PM · View previous versions
Wider and faster lenses are more likely to have higher radiation. If you are concerned and want to know if it's radioactive, place the lens on a piece of unexposed B&W film (Faster ASA / ISO should work better) in a dark closet for 24 hours. Have the sheet of film developed. If you see streaking or other strange marks where the lens was, you have a radioactive lens.
If you are worried about the radiation, you should remove all of your smoke detectors while you are at it because they emit radiation as well.
In truth, alpha particles are stopped by just about anything and everything, including a few inches of air. Unless you are holding the back of one of these lenses directly up to your eye, your camera and hands will probably be blocking any harmful radiation.
While microwave ovens use non-ionizing radiation, high frequency radio waves are very harmful to soft tissue. I'd be more worried about watching my food cook in one than being worried about the dose of alpha and beta particles that may be hitting my face from my lens.
Edited on Dec 17, 2010 at 04:36 PM · View previous versions
Dec 17, 2010 at 03:38 PM
p.3 #4Beware Radioactive Lenses
Aaron D wrote:
I'd be more worried about watching my food cook in one than being worried about the dose of alpha particles that may be hitting my face from my lens.
I wouldn't worry about anything escaping from your microwave. That's what the metal mesh on the window is for. It's opaque to microwaves.
I'd be far more worried that whatever I was cooking exploded and created shrapnel. Or just creating a mess that I have to clean up in the microwave
I'd be more worried about watching my food cook in one than being worried about the dose of alpha particles that may be hitting my face from my lens.
I wouldn't worry about anything escaping from your microwave. That's what the metal mesh on the window is for. It's opaque to microwaves.
I'd be far more worried that whatever I was cooking exploded and created shrapnel. Or just creating a mess that I have to clean up in the microwave
Dec 17, 2010 at 03:41 PM
p.3 #5Beware Radioactive Lenses
anytime you get hard numbers about cancer risk and radiation exposure take then with a grain of salt... yes, the more you're exposed the worst it is but in terms of % risk there are MANY other factors that influence your likelihood of developing cancer then just plain old exposure... anyway, I guess take home message is if you care about very low doses of radiation then here's another source to worry about... if you don't then just keep eating healthy and enjoying life (and hope you have good genes )
kidtexas wrote:
Hmm, I might have extra access to the book since I'm at an academic institution. I quoted the relevant statistics though. Extra cases of getting cancer out of 100,000 from 10 rem is 800 (0.8% increase), extra cases resulting in death is 400 (0.4% increase). The baseline percentages of cancer is 44%/22% for cases/death.
Also: "At doses less than 40 times the average yearly background exposure (100 mSv), statistical limitations make it difficult to evaluate cancer risk in humans."
(and hope you have good genes )kidtexas wrote:
Hmm, I might have extra access to the book since I'm at an academic institution. I quoted the relevant statistics though. Extra cases of getting cancer out of 100,000 from 10 rem is 800 (0.8% increase), extra cases resulting in death is 400 (0.4% increase). The baseline percentages of cancer is 44%/22% for cases/death.
Also: "At doses less than 40 times the average yearly background exposure (100 mSv), statistical limitations make it difficult to evaluate cancer risk in humans."
Dec 17, 2010 at 03:44 PM
p.3 #6Beware Radioactive Lenses
morpheus2891 wrote:
anytime you get hard numbers about cancer risk and radiation exposure take then with a grain of salt... yes, the more you're exposed the worst it is but in terms of % risk there are MANY other factors that influence your likelihood of developing cancer then just plain old exposure...
Exactly but statistical studies like this are the best we have. And that report is one of several in a line of pretty comprehensive studies.
I think the take home message is unfortunately roughly 40% of us are going to develop cancer with no particular known factor responsible. And the estimates from reasonably high dosages of radiation that most of us would avoid (10 rem) do not suddenly double our chances of getting cancer (to 80%). It's down in the single percent or lower increase.
Not that that is reassuring if you are in that small portion of the population.
anytime you get hard numbers about cancer risk and radiation exposure take then with a grain of salt... yes, the more you're exposed the worst it is but in terms of % risk there are MANY other factors that influence your likelihood of developing cancer then just plain old exposure...
Exactly but statistical studies like this are the best we have. And that report is one of several in a line of pretty comprehensive studies.
I think the take home message is unfortunately roughly 40% of us are going to develop cancer with no particular known factor responsible. And the estimates from reasonably high dosages of radiation that most of us would avoid (10 rem) do not suddenly double our chances of getting cancer (to 80%). It's down in the single percent or lower increase.
Not that that is reassuring if you are in that small portion of the population.
Dec 17, 2010 at 03:59 PM
p.3 #7Beware Radioactive Lenses
kidtexas wrote:
I wouldn't worry about anything escaping from your microwave. That's what the metal mesh on the window is for. It's opaque to microwaves.
I'd be far more worried that whatever I was cooking exploded and created shrapnel. Or just creating a mess that I have to clean up in the microwave
I'd be more worried about the shrapnel than the microwaves themselves as well. We are subjected to more EM radiation from our cell phones, cordless phones, wireless computer networks and power lines.
As an interesting side note, fire up Google Earth and enable the satellite tracker filter. Look at all of those satellites in orbit. Now, try and comprehend the amount of EM radiation flooding into our atmosphere by all of these.
Long story short, we are constantly bombarded by harmful EM radiation from things such as these, as well as from space, our own sun, and the rock we build our homes on. If one is concerned about his camera lens being harmful, then he should take all of these other forms of radiation into account and move to the moon.
Alpha particles are generally not considered dangerous unless ingested or inhaled. As mentioned earlier, you'd have to grind up the lens and eat or snort it. Beta particles are the ones that mutate cellular structure. Ironically, they are also the particles used to treat cancer with radioactive therapy. These have more "penetrating" power than alpha particles. Still, camera should shield the eyes from most, if not all, of these. For cameras employing Th-232 treated lenses, only the gamma rays result in a dose to the lens of the eye.
I'd still be more worried about all the other background radiation I posted about than worried about my lens giving me cataracts.
**EDIT**
Receiving a good bill of health from your doctor only means you are dying at the slowest rate possible.
Edited on Dec 17, 2010 at 04:22 PM · View previous versions
Aaron D wrote
I'd be more worried about watching my food cook in one than being worried about the dose of alpha particles that may be hitting my face from my lens.I'd be far more worried that whatever I was cooking exploded and created shrapnel. Or just creating a mess that I have to clean up in the microwave
I'd be more worried about the shrapnel than the microwaves themselves as well. We are subjected to more EM radiation from our cell phones, cordless phones, wireless computer networks and power lines.
As an interesting side note, fire up Google Earth and enable the satellite tracker filter. Look at all of those satellites in orbit. Now, try and comprehend the amount of EM radiation flooding into our atmosphere by all of these.
Long story short, we are constantly bombarded by harmful EM radiation from things such as these, as well as from space, our own sun, and the rock we build our homes on. If one is concerned about his camera lens being harmful, then he should take all of these other forms of radiation into account and move to the moon.
Alpha particles are generally not considered dangerous unless ingested or inhaled. As mentioned earlier, you'd have to grind up the lens and eat or snort it. Beta particles are the ones that mutate cellular structure. Ironically, they are also the particles used to treat cancer with radioactive therapy. These have more "penetrating" power than alpha particles. Still, camera should shield the eyes from most, if not all, of these. For cameras employing Th-232 treated lenses, only the gamma rays result in a dose to the lens of the eye.
I'd still be more worried about all the other background radiation I posted about than worried about my lens giving me cataracts.
**EDIT**
Receiving a good bill of health from your doctor only means you are dying at the slowest rate possible.
Edited on Dec 17, 2010 at 04:22 PM · View previous versions
Dec 17, 2010 at 04:04 PM
p.3 #8Beware Radioactive Lenses
AmbientMike wrote:
If I read that table right, 45% of males will have cancer in their lifetime. Is that true?
sadly, everybody gets cancer if they live long enough. it's only people that manage to die of something else at a younger age who don't get cancer.
AmbientMike wrote:
Todd, I knew somebody would think this! sebboh, the 55/1.2 has the potential to have this? might pass on that one or get it tested if I get one.
i thought all copies of the zuiko 55/1.2 had it, but i could be wrong. most people agree that the zuiko 50/1.2 is better anyway (none of those are radioactive).
another radioactive lens that everybody should send to me for proper disposal of is the rokkor 58/1.2 with the scalloped focus ring (a few other old rokkors as well i believe).
If I read that table right, 45% of males will have cancer in their lifetime. Is that true?
sadly, everybody gets cancer if they live long enough. it's only people that manage to die of something else at a younger age who don't get cancer.
AmbientMike wrote:
Todd, I knew somebody would think this!
sebboh, the 55/1.2 has the potential to have this? might pass on that one or get it tested if I get one.i thought all copies of the zuiko 55/1.2 had it, but i could be wrong. most people agree that the zuiko 50/1.2 is better anyway (none of those are radioactive).
another radioactive lens that everybody should send to me for proper disposal of is the rokkor 58/1.2 with the scalloped focus ring (a few other old rokkors as well i believe).
Dec 17, 2010 at 04:07 PM
p.3 #9Beware Radioactive Lenses
radon.
Herb...
morpheus2891 wrote:
so basically go live in a cave
Herb...
morpheus2891 wrote:
so basically go live in a cave
Dec 17, 2010 at 04:12 PM
p.3 #10Beware Radioactive Lenses
LMAO... guess we're just screwed no matter what! 
HerbChong wrote:
radon.
Herb...
HerbChong wrote:
radon.
Herb...
morpheus2891 wrote
so basically go live in a caveDec 17, 2010 at 04:34 PM
p.3 #11Beware Radioactive Lenses
kidtexas wrote:
Exactly but statistical studies like this are the best we have. And that report is one of several in a line of pretty comprehensive studies.
I think the take home message is unfortunately roughly 40% of us are going to develop cancer with no particular known factor responsible. And the estimates from reasonably high dosages of radiation that most of us would avoid (10 rem) do not suddenly double our chances of getting cancer (to 80%). It's down in the single percent or lower increase.
Not that that is reassuring if you are in that small portion of the population.
Right, but in any case, we all have a 100% chance of dying.
Problem is that all this statistical stuff is not saying anything about you or your future. So starting to worry about certain things like the radioactive lenses is a little bit stretched imho. Plus, this is what we know today. Tomorow new things and new statistics will emerge and somebody in hundred years from now might ask : how did they survive ? Same thing goes with all the chemical stuff that you had in the last half of the XX century. And the list goes on.
Exactly but statistical studies like this are the best we have. And that report is one of several in a line of pretty comprehensive studies.
I think the take home message is unfortunately roughly 40% of us are going to develop cancer with no particular known factor responsible. And the estimates from reasonably high dosages of radiation that most of us would avoid (10 rem) do not suddenly double our chances of getting cancer (to 80%). It's down in the single percent or lower increase.
Not that that is reassuring if you are in that small portion of the population.
Right, but in any case, we all have a 100% chance of dying.
Problem is that all this statistical stuff is not saying anything about you or your future. So starting to worry about certain things like the radioactive lenses is a little bit stretched imho. Plus, this is what we know today. Tomorow new things and new statistics will emerge and somebody in hundred years from now might ask : how did they survive ? Same thing goes with all the chemical stuff that you had in the last half of the XX century. And the list goes on.
Dec 17, 2010 at 04:36 PM
p.3 #12Beware Radioactive Lenses
The most common causes to death in Sweden are Car-accidents, Liquor and Radioactive Canon FD and Pentax m42 lenses
Dec 17, 2010 at 04:44 PM
p.3 #13Beware Radioactive Lenses
Lars Johnsson wrote:
The most common causes to death in Sweden are... and Radioactive Canon FD and Pentax m42 lenses
That's where all the background radiation in Sweden comes from! I was wondering if you would comment Lars.
The most common causes to death in Sweden are... and Radioactive Canon FD and Pentax m42 lenses
That's where all the background radiation in Sweden comes from! I was wondering if you would comment Lars.
Dec 17, 2010 at 04:57 PM
p.3 #14Beware Radioactive Lenses
I think I need to shorten all my lens straps, just to be on the safe side.
Dec 17, 2010 at 04:59 PM
p.3 #15Beware Radioactive Lenses
sebboh wrote:
another radioactive lens that everybody should send to me for proper disposal of is the rokkor 58/1.2 with the scalloped focus ring (a few other old rokkors as well i believe).
To be more precise, all-metal versions (I've had scalloped potatoes, but lenses?) with serial numbers between 200xxxx and 255xxxx (not sure precisely where the thorium version ended but I've never seen or heard of a radioactive 257xxxx or greater. Some 256xxxx are radioactive, but maybe not all).
another radioactive lens that everybody should send to me for proper disposal of is the rokkor 58/1.2 with the scalloped focus ring (a few other old rokkors as well i believe).
To be more precise, all-metal versions (I've had scalloped potatoes, but lenses?) with serial numbers between 200xxxx and 255xxxx (not sure precisely where the thorium version ended but I've never seen or heard of a radioactive 257xxxx or greater. Some 256xxxx are radioactive, but maybe not all).
Dec 17, 2010 at 05:00 PM
p.3 #16Beware Radioactive Lenses
sebboh wrote:
another radioactive lens that everybody should send to me for proper disposal of is the rokkor 58/1.2 with the scalloped focus ring (a few other old rokkors as well i believe).
Yep, that was the source/cause of the last time we had a thread on this subject about a yr or two ago. along with Paul's FD28 I think.
Nope, can't have my radioactive Rokkor 58/1.2 copy. I mostly use my newer, non-radioactive copy of the lens though. I better get a lead lens case for my radioactive one.
another radioactive lens that everybody should send to me for proper disposal of is the rokkor 58/1.2 with the scalloped focus ring (a few other old rokkors as well i believe).
Yep, that was the source/cause of the last time we had a thread on this subject about a yr or two ago. along with Paul's FD28 I think.
Nope, can't have my radioactive Rokkor 58/1.2 copy. I mostly use my newer, non-radioactive copy of the lens though. I better get a lead lens case for my radioactive one.
Dec 17, 2010 at 05:06 PM
p.3 #17Beware Radioactive Lenses
cogitech wrote:
To be more precise, all-metal versions (I've had scalloped potatoes, but lenses?) with serial numbers between 200xxxx and 256xxxx (not sure precisely where the thorium version ended but I've never seen or heard of a radioactive 257xxxx or greater).
"scalloped" refers to the way the metal focus rings are machined while the rubber focus rings are ribbed or something.
sebboh wrote
another radioactive lens that everybody should send to me for proper disposal of is the rokkor 58/1.2 with the scalloped focus ring (a few other old rokkors as well i believe)."scalloped" refers to the way the metal focus rings are machined while the rubber focus rings are ribbed or something.
Dec 17, 2010 at 05:06 PM
p.3 #18Beware Radioactive Lenses
wayne seltzer wrote:
Nope, can't have my radioactive Rokkor 58/1.2 copy. I mostly use my newer, non-radioactive copy of the lens though. I better get a lead lens case for my radioactive one.
how come? (you mostly use the newer one, not how come you won't give me your older one)
also, how many lenses do you have multiple copies of?
Nope, can't have my radioactive Rokkor 58/1.2 copy. I mostly use my newer, non-radioactive copy of the lens though. I better get a lead lens case for my radioactive one.
how come? (you mostly use the newer one, not how come you won't give me your older one
)also, how many lenses do you have multiple copies of?
Dec 17, 2010 at 05:08 PM
p.3 #19Beware Radioactive Lenses
I do not know if the 58/1.2 is radioactive but it has been bad for my nerves since I did not that lens and every time I tried I was not able to get a good deal on it. Now I am skipping that one - will for sure be good for my health
Dec 17, 2010 at 05:13 PM
p.3 #20Beware Radioactive Lenses
sebboh wrote:
"scalloped" refers to the way the metal focus rings are machined while the rubber focus rings are ribbed or something.
I was making a little joke. I'm not a comedian, it seems
"scalloped" refers to the way the metal focus rings are machined while the rubber focus rings are ribbed or something.
I was making a little joke. I'm not a comedian, it seems
Dec 17, 2010 at 05:14 PM