Ed's advice is right on the spot. Regarding bleaching the Aero Ektar lens, this works fine with a simple IKEA Jansjö LED lamp for 10 EUR/USD. The lamp was placed appr. 1"/2.5cm above the rear element. The maximum temperature reached at the rear element was less than 40°C/104°F.
After 10 days, the bleaching process seemed to be more or less complete, as can be seen in the image below:
Cheers
Andreas
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