With the releases of Titanic in 3D, the world is a buzz with how clear and crisp the film still is in 3D… and this is how.
“THE ship still sinks,” the director James Cameron said back in October when he was in New York to present some scenes from the updated “Titanic” to the news media. While the version returning to theaters on Wednesday is the same cut that was released 15 years ago, the film’s 4K digital remastering and its meticulous 3-D conversion make for a fresh visual experience. The process spanned over 60 weeks and cost about $18 million to achieve a look that seems as if it had been originally shot with 3-D cameras.
Mr. Cameron worked with the conversion company Stereo D and, utilizing his experience with shooting in 3-D over the past decade, supervised the process along with his in-house staff. The frame below, with Kate Winslet and Billy Zane, shows the lead character Rose’s arrival to the ship and is an example of one of the shots from the film where 3-D looks the most dynamic. Mr. Cameron explains elements of the work that went into the project. — MEKADO MURPHY
Filling In ShadowsWhen creating dimensionality in 3-D, the artists at Stereo D had to generate separate images that would mimic left- and right-eye views. This results in one of the biggest challenges in conversion: replacing shadows of missing information. To illustrate, if you put a hand in front of your face and focus on a background image, when you close one eye, you see one version of that image. If you switch eyes, a part of the object that was covered by your hand is revealed. The same happens in 3-D images, but for a film shot in 2-D that second eye view doesn’t exist, and a blank space is left. “That information is made up by taking pixels from adjacent areas of the frame or from later frames,” Mr. Cameron said. “They have to construct a new image that fits into that shadow.” Here, parts of the ship were taken from other frames and painted in to fill the blank space.
Adjusting DepthIn addition to the complexities of this shot Mr. Cameron said one of the more difficult elements to get accurate in 3-D was creating depth between a person and one who is closer to the camera, like in an over-the-shoulder shot. “Typically in these shots the artists weren’t giving me enough depth between the foreground person who’s out of focus and has their back turned and the mid-ground person who is the main subject,” Mr. Cameron said. “We had to push them to give us the correct spatial arrangement of characters in the frame.” There were also places where he thought the 3-D should be reined in, namely wide shots of objects from a long distance. When the artists would take a wide shot where the entire ship was visible and make it 3-D, he found that it looked like a miniature. “I would have to dial them back the farther we were from the subject,” he said.
Creating a Depth MapThis shot, when originally filmed, was made with a long lens from fairly far away, creating a telephoto view with a variety of people in the frame and much of the background in focus. Mr. Cameron was aiming for a sense of depth even then, and his shooting style was favorable to conversion. For the 3-D, artists isolated each object and placed it on what Mr. Cameron called a “depth map.” Each item was assigned a level of depth, making for various “depth planes.” “We had to take extra care,” he said. “You have to create dimensionality in the characters’ bodies and their faces. But you also have the foreground crosses of extras. Those extras need to be pulled well forward into a completely different depth plane.” What results on the screen is a detailed shot with the extras in the foreground seeming to pass directly in front of the viewer.
RotoscopingTo isolate objects in the frame for depth, the artists at Stereo D would use a process called rotoscoping. They would go in and draw lines around each object that needed to be on a different depth plane. “So the edge of Kate’s shoulder, where it stops being pixels of Kate and starts being pixels of the background beyond her, has to be defined,” Mr. Cameron said. “Also the shape of her body and her face and her hat, all have to be defined as well.” This painstaking process is done for each frame and each eye view.
Then it all must be reviewed. “My staff would spend 20 to 30 hours a week reviewing the work of the artists,” he said. “And then I would spend four or five hours a week reviewing the work of my staff that acted as a filter to me. I’m not whining. I just want people to understand the scope of this.”
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