Toronto-based stereographer Demetri Portelli graduated from the University of Toronto, Canada in 1995. His most recent work was on Martin Scorsese's Hugo, said to be one of the few truly enjoyable stereoscopic 3D experiences for movie-goers. The Canadian stereographer has already won the Lumiere Award for Best Live Action Stereography from the International 3D Society for his work on Hugo.Since directing music videos and short films in the early part of his career he has dedicated himself completely to the technology and the art of the stereoscopic 3D motion picture. His work hasn't stopped at Hugo, either, as he introduced 3D capture to British cinematographer John Mathesion for the movie 47 Ronin featuring Keanu Reeves and that is set to be released in November 2012. He also has a long history of other film credits that you can view on IMDB.
Toronto is a great place for 3D
Portelli referenced his Toronto roots as a great place to play around with a camera and that some of the keys to successful 3D production is preparation, figuring out angles for shots beforehand which leads to consistency throughout production, and shooting 3D differently than you would shoot 2D. It certainly didn't hurt to work with legendary Oscar award-winning producer Martin Scorsese either.
Portelli said that the major difference between Hugo's 3D production and many others is that under Scorsese the right team of people were assembled that could work together for the most effective 3D shooting experience.
About the stereographer's job
Stereographer Demetri Portelli augmented his career as cameraman/First AC to train under Vince Pace. "Stereographer is a new job, one that people weren't sure needed to exist on a film set," states Portelli, "but when your cinematographer is on the eyepiece, you protect his work [and] guarantee 3D technical consistency, complementing his vision and style. My background made it possible to establish a vital partnership with Richardson's longtime First AC, Gregor Tavenner, who embraced the technology and made valuable contributions to the process of shooting with 3D rigs. Since Avatar, serious filmmakers recognize that in order to make a quality 3D cinema experience, they must capture live. Using the appropriate rig and the right lenses will capture a dimensionalized environment, enabling the viewer to be immersed in the illusion."
Portelli feels the role of the stereographer, working in conjunction with the entire camera crew, involves employing consistency and workmanship for 3D imaging to provide choice and opportunity for the filmmaker, an approach similar to other key established jobs on a film set. "Stereographers must remember the IO [interocular] and convergence on preceding shots, take proper notes, and pay attention to new lighting and moving elements," explains Portelli. "I know what I'm going to do for IO and convergence on the closeup, and how that will differ during the track back to a wide shot, but more important is why the depth must be adjusted dynamically, [and] when and where; you've got to balance depth consistently so the scene will cut together. There's a sweet spot to be found in creating and finding the right 3D depth."
"Finding the correct depth isn't mathematical, but a matter of trying many different techniques to find optimum IO settings and range. Being hands-on is vital. If Richardson, who's very organic and intuitive, decides spontaneously to push in close on Hugo, he must rely on the convergence puller to adjust depth immediately, or else the boy's face may come right off the screen, gaining undesirable exaggerated features. A saving grace is that convergence can be altered somewhat after the fact; shots and sequences can and should receive a proper 'stereo DI viewing session,' where the final edit may dictate a change of screen plane to soften or enhance the 3D." (from a paper in HDVideoPro)