David Hockney: Secret Knowledge 23 years old

Artist David Hockney discusses his theory that artists were secretly using optical devices such as mirrors and lenses in creating their work as early as the 15th century.

Credits

David Hockney: Secret Knowledge Cast

Name	Character
David Hockney He was 66, now 87 years old	as himself

David Hockney: Secret Knowledge Crew

Name	Department