Radioactive lenses

I'm aware that some older MF lenses (e.g. the Takumar 55mm) are very mildly radioactive. The relative importance of this has been discussed to death in plenty of places, but does anyone know whether the Helios 44M series has this 'attribute'? :p

I've had plenty of Helios 44's and never noticed any yellowing of the elements on any of them, so I'd guess not.

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Joining the Q

I believe it was only the Super Takumar's that had the radio active elements, I owned a 50mm 1.4 super Tak that had turned yellow and I didn't like the yellowy cast it left on my pics.

You need to be careful if using one of these lenses with tubes, I was taking pics of bugs at close range and they were all dropping dead of radiation sickness, One good thing though is the batteries in your camera never go flat

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Camera:|K-7|
Pentax Lenses:|DA12-24/f4 ED AL|DA35Ltd Macro|FA31Ltd|FA77Ltd|FA50/1.4|F70-210|FA20-35 f4/AL|A*200/f4 Macro ED|A50/1.7|A50 Macro f2.8|1.7xAF adapter|
Voigtlander|125/f2.5SL Macro APO Lanthar|
Sigma Lenses:|EX DG 100-300 f4|2X & 1.4X TC|
Flashes:|AF540FGZx2|RingFlash AF160FC|

just watch out for greenpeace

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you don't have to be mad to post here



but it does help

I've got a Helios 44m on an old Zenit EM, and haven't ntoiced any yellowing, and that's as recently as a couple of days ago when I last used it. I've not been feeling too well today though...

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If you can't say something nice about Pentax, you won't say anything at all.

Apparently.

Clarky, is that how you get them keep still?...

My CZJ Biometar 80mm F2.8 P6 has very slight yellowing. Didn't notice until it was mentioned in some forum.
bb2

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K5, K20D, Bigma, Sigma EX 105, Sigma EX 10-20, Sigma EX 28-70 F2.8, Sigma Ex 1.4TC,
Pentax 135 F3.5, Pentax 30mm F2.8 , Pentax 50mm F1.7, Pentax 55mm F1.8,
Super Taks: 35mm F3.5, 50mm F1.4, 135mm F3.5, 200mm F4
Vivitar TX 200mm F3.5,Vivitar (Komine)135mm f2.8, Vivitar 2X TC, Vivitar T4 400mm F6.3
Tamron SP 35-80,80-210 F3.8, Helios 44M, Mir 1B 37mm F2.8, Jupiter 9 85mm F2, Chinon 28mm F2.8, 3M-5A 500mm F8 etc etc

I think it's all to do with the use of rare earth glasses in the construction.

I don't think users of radioactive lenses are going to start glowing in the dark.

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Best regards, John

Just as well, it might ruin the look of their night shots...

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If you can't say something nice about Pentax, you won't say anything at all.

Apparently.

I have read that exposing lenses to strong UV can kill the yellow tinge. The site suggested leaving them on a windowsill in sunlight, however I'd be a bit worried about the magnifying effect of the lens burning items below it!

Not sure what you can do about the radiation however - lead-lined lens cases maybe?

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Matt

Shooting the Welsh Wilderness with K-m, KX, MX, ME Super and assorted lenses.

Perhaps you should wear a 'film badge' to assess what sort of a dose you have received!!

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All five minute jobs take a minimum of eight hours!