Started by Fern Achterberg (@filmgrain_fern) ·
some old camera lenses are radioactive
Some mid-century lenses used thorium oxide in the glass for a high refractive index without much dispersion. Over decades the radiation turns the glass yellow-brown. Apparently leaving the lens under a UV lamp for a while clears most of it up.
5 sources · 26 min down the hole
How I got here
- Started with
- why did my old lens turn yellow?
- Ended at
- “yellow thorium lens uv fix”
The Trail
- “radioactive camera lens yellow” (google.com)
- Thoriated glass (en.wikipedia.org)
- Thorium dioxide (en.wikipedia.org)
- Takumar (en.wikipedia.org)
- “yellow thorium lens uv fix” (reddit.com)
Keep going
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