Secret Knowledge: Rediscovering the Lost Techniques of the Old Masters by David Hockney.

The veteran British artist died last week at the age of 88. He was working (usually on an iPad) right to the end of his life, including a vast frieze inspired by the Bayeux Tapestry.

This 2001 book argues that the Renaissance greats such as Caravaggio and Vermeer used optical devices like the camera obscura to achieve their startling realism, just as he much later would use technology to boost his own work; it is “a short and thrilling book with big … things to say,” The Guardian wrote at the time. Buy Secret Knowledge from your local bookstore.