The result -- The Up Films: The Speed of Life.
As I wrote in the article, "The point was not to take an endurance test, but to experience what captured time, 49 years of it, was like and what insights might be gleaned from viewing it this way."
While you're there, you might also check out Five Questions for Michael Apted. I am very grateful to have been given the opportunity to ask him a few things about these astonishing films.
Thanks to the fine folks at Filmmaker Magazine and First Run Features for all of their help.