Greetings,

The subject of radioactivity and Aero Ektars was addressed on the helpboard a few weeks ago. There is some very interesting coverage on the subject at the following website address (it should be noted that a hyperlink will take you to an Ektar page that has a lot of interesting information):

http://people.smu.edu/rmonagha/mf/radioactive.html

Happy reading!

JP Mose

Quote:

On 2001-10-26 10:38, jpmose wrote: Greetings, The subject of radioactivity and Aero Ektars was addressed on the helpboard a few weeks ago. There is some very interesting coverage on the subject at the following website address (it should be noted that a hyperlink will take you to an Ektar page that has a lot of interesting information): http://people.smu.edu/rmonagha/mf/radioactive.html Happy reading! JP Mose

I know it's been a while since your post, but I just had to now respond...

I found all this info very interesting. Oddly enough, it was a bubble conversation that made me look up some Minolta documentation because I thought there was a mention there of how they controlled bubbles in their glass. What I found was a PR comment about how they used "rare earth elemnts" including thorium and lanthanum! Since my LF lenses showed no signs of radioactivity, I thought I was 'safe'. Now I checked my other lenses... All okay, even the Minoltas, except one Sigma! An 18mm old lens is deffinitely radioactive! Upwards of 2 mR/hr at close range. Not much in the grand scheme of things, but a good 100 times background levels. Maybe that's why that lens always performed so well? But I will be seriously considering replacing it now. Thanks! And maybe a reminder that most people should check theirs too? It's not just LF lenses!

Rich...