Which of the following is NOT a primary limitation of camera-based motion capture (MOCAP) systems?

• A. Limited to laboratory settings.
• B. Difficulty replicating natural behaviors.
• C. The requirement for an unobstructed view of the subject.
• D. Not requiring a setup; works outdoors.

Answer: (D)

Camera-based motion capture relies on a network of cameras and often reflective markers to reconstruct 3D motion. The real challenges come from needing to maintain an unobstructed line of sight to all markers, which is hard in cluttered or outdoor environments; you must carefully set up and calibrate multiple cameras to cover the capture volume, and lighting conditions need to be stable. Wearing markers or suits can also influence how someone moves, making it difficult to capture truly natural behavior. In short, outdoor use and avoiding any setup would be strengths, not limitations, which is why that statement is not a true limitation of camera-based MOCAP. The other points reflect genuine constraints researchers and clinicians face when using these systems.