Radioactive lens (SMC Takumar 55/1.8) measured with Polaron-Pripyat and RKSB-104 dosimeters

http://c4r0.skrzynka.org/

This is an SMC Takumar 55/1.8 that has a thorium doped lenses. Thorium was used to obtain larger refraction ratio and keep relatively low dispersion at the same time.

Radiation was measured with beta shields removed, so both gamma quants and beta particles were counted. Dose equivalent rate is almost 30uSv/h (200 times background radiation in my area). RKSB-104 (GORIN) shows only 20uSv/h because it has two G-M tubes on opposite sides of the casing, so only one tube was exposed to the radiation (the lens is 3-4cm in diameter). Polaron has two tubes also but both are placed on one side, so they both were exposed to the radiation.

Category:

Science & Technology

Tags:

• radioactive
• lens
• smc
• takumar
• polaron
• pripyat
• rksb-104
• radiation
• dosimeter
• gamma
• beta
• yt:quality=high

[fabiodeconto]

wath kind of radioactive material is the lens made of?

thorium is gamma and beta emiter?

[c4r0hv]

@fabiodeconto

It's said in the video description - it's thorium.

[unbee73]

omg i have a Pentax Asahi 1.4 SMC Takumar on my desk 20 cm in front of me right now.... what to do? :(

[c4r0hv]

@unbee73

You're irradiated anyway, so there's not much you can do. Just take it and burry it at least 2m under the ground in some area where there's no people. Then make sure noone will ever walk into your room and touch your desk. Then, since you're already irradiated anyway, maybe it would be a good idea to fly to Fukushima and help those guys cleaning the mess - this way you would contribute to the safety of future generations, if you do that it would be a benefit for the whole human race.

[YevGus]

So, why you keep it in your house? it's better to get rid of this shit! :-)))

[c4r0hv]

@YevGus

I keep it in my house and USE IT because it's a good lens. And I think it's not dangerous.

[c4r0hv]

@Christoff87

As you noticed, alpha particles (technically it's not radiation) hardly penetrates anything - those are not alpha particles that are counted in the video ;)

[pooh1234567890]

@c4r0hv That was hilarious, thanks!

[doserdog]

@c4r0hv Alpha particles are most certainly radiation as they are given off by nuclear decay. Once again you said something very dumb.

[doserdog]

@c4r0hv That's the dumbest thing I've ever heard...

[PocketElectronic]

Shit, where'd you get it from? Chernobyl?

[xxxASOTxxx]

как так???

[unbee73]

@c4r0hv OMG .... it still there .... but hey, good idea ... i'll fly to Fukushima and help them :D ^^