Correcting the rolling shutter effect in a video analysis experiment

The rolling shutter effect, a well-known source of distortion in pictures captured with sensors that acquire the image line by line rather than at a single instant, significantly impacts video analysis, a common technique in introductory physics labs for studying motion. When a decelerating rotational motion is recorded with such sensors, the measured angular velocity exhibits pronounced oscillations, rather than a uniform decrease. However, these artifacts can be eliminated by advancing or retarding the timestamp of each video frame. This correction, which involves calculating the derivative of data with non-uniformly spaced timestamps (a task achievable through straightforward methods), provides students with a valuable opportunity to understand the necessity of identifying and correcting sensor-induced artifacts. While the rolling shutter effect also introduces errors in projectile motion experiments, including a 4% overestimation of the free-fall acceleration g , its impact is less pronounced than in rotational motion scenarios.