At an auction in Vienna, Austria, in 2012, the world's most expensive camera sold for $2.8 million. The camera was a Leica 35mm film model, which was one of only 25 produced in 1923 for testing.
In 2012, only 12 of the rare camera models were believed to still exist.
https://medium.com/@kevinshau/on-leonardo-da-vincis-salvator-mundi-is-it-authent
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