We take a lot for granted in the digital era, particularly the automation of a lot of functions. In the early days of film, everything was fully manual, and even one parameter set incorrectly could ruin an entire roll. Later in the 20th century, a standard called DX (Digital indeX) was introduced, and it automated a lot of settings, reducing errors and making photography more accessible to amateurs and casual users. How did it work? This neat video takes you behind the scenes of the surprisingly sophisticated system.