MrSeb writes: "From the story: 'Not everyone likes 3D movies, and almost everyone agrees that traditional movies later converted to 3D have been disappointing. Until now, James Cameron, famed director and now also deep sea explorer, agreed with them. He has been a harsh critic of 3D film conversions, except that he has now spent a reported $18 million converting his blockbuster movie, Titantic, to 3D. The re-release is timed to coincide with the movie’s 15th anniversary and the 100th anniversary of the Titanic’s sinking. This herculean effort inspired us to take a closer look at how a movie gets converted to 3D after it has already been shot, and what makes Cameron’s effort so daunting.' ExtremeTech looks at the primary way of managing depth in 3D films (parallax), how you add depth to a movie that was originally filmed in 2D, and some of the software (both computer and human-brain) difficulties that Cameron had to overcome in the more-than-two-year process to convert Titanic into 3D."