Panasonic AG-HMX100 3D Production Post White Paper - Page 1

3D Production and Post Barry Clark 03-26-10 Real World 3D When a viewer's eyes focus on a real object, they automatically converge on the object. From the separate perspectives seen by the two eyes, the viewer's brain fuses a coherent 3D image of the object. All of the objects that the viewer sees in 3D occupy a cone that is bounded by the edges of the overlapping fields of focus and convergence of the viewer's eyes. Everything outside of this cone is seen by the viewer in 2D. As the viewer's eyes focus on progressively more distant objects, the zone of convergence shifts with the zone of focus and the cone shrinks in width until an outer limit of distance is reached-a distance of 100-200 yards in the average adult-beyond which the viewer can no longer distinguish the perspectives seen by the left and right eyes. Everything that is located further away from the viewer seems to lie on a flat, 2D plane. To judge the relative position in space of objects that lie beyond this stereoscopic limit, a viewer must rely on monoscopic depth cues, including motion cues (nearby objects seem to shift position more rapidly than distant objects), atmospheric cues (the hue of objects shifts toward blue as they move into the distance), and occlusion cues (near objects obscure the view of more distant objects). Fig.1 - Real World 3D Simulated 3D The experience of viewing a 3D film is significantly different from the way a viewer sees 3D in the real world. The most obvious differences between real world 3D and the simulated 3D that is viewed on a screen are a consequence of the fixed depth-of-field and the fixed point-of-view of the lenses that capture the images. As a result of these constraints, viewers watching simulated 3D can no longer alter their point-of-view simply by shifting the position of their heads, as they can in the real world. And when turning their attention from one object of interest to another, they can no longer simply refocus their eyes, as they can in the real world. In a 3D film, the point-of-view and the focus are invariables established on the set. In addition, when looking at a 3D object displayed on a screen, a viewer's eyes must focus on the screen while, at the same time, they converge on a point in space that may be located beyond the screen, on the screen, or in front of the screen. As a result of this process-which differs from the way a viewer sees the world- the viewer has the sensation that the 3D object is located either in the space beyond the screen, on the screen plane, or in front of the screen. A 3D object that appears to be located on the screen plane is relatively easy for a viewer to watch. But, over time, a viewer may experience eyestrain from the effort involved in fusing coherent 3D images of objects that reside far beyond or far in front of the screen.