Quote Originally Posted by Tony D View Post
From what i understand the Aero-Ektar lens contain glass elements made of Thorium, which is radioactive and causes internal fogging.

Not fogging. Lens elements made of thoriated glass eventually yellow. They're still clear. The yellowing can be removed by letting the lens bask for a while, sometimes a long while, under a UV lamp.

Aero Ektars aren't the only lenses that contain radioactive elements. I've cleared three TTH tessar type process lenses and one Repro Claron with a compact 20w UV-B fluorescent. The process took nearly a month with that dim little bulb. Some people have reported quicker clearing by setting lenses to bask in the sun. I was reluctant to do that because of the crud that falls from the sky.