 Rapid cuts between two different viewpoints can be uncomfortable for the viewer, so directors may lengthen the transition or provide images with intermediate depth between two extremes to "rest" the viewer's eyes.3D images are most effective if the cameras are at a low angle of view, simulating presence of the viewer at the event; this can present problems with people or structures blocking the view of the event.While fewer camera locations are required, the overall number of cameras is similar to a 2D broadcast because each position needs two cameras.