Bending SpokesJeffrey LiuAward: Top 100
School: amador valley high school My photo depicts the unique curvature of bicycle spokes due to the rolling shutter effect. The rolling shutter effect can be achieved through using a rolling shutter, which is found in most modern cameras. A rolling shutter, instead of taking a picture all in one go, takes many strips consecutively of the scene and piecing them together at the end. Rolling shutters are superior to global shutters in that they provide extreme speeds. However, in cases like a fast moving bicycle tire, curved artifacts can be found. As the wheel spins around, the shuttering system is unable to capture the spokes as a straight line; The spokes move with the shutter. This creates beautiful swept areas in place of the predictable straight lines. Furthermore, even though the angular velocity is the same throughout the whole spoke, the tangential velocity increases as the radius of the spoke increases. This means that the spoke moves quicker on the edge than near the middle. Because the near-center spots spin slower, the shutter is able to capture a sharper curve whereas the edges have a lighter curve, creating a parabolic shape. Using a quick shutter speed can capture sharp, defined lines. However, using a slower shutter speed allowed me to capture warm light swept areas on the dark backdrop. The swept areas are achieved as the rolling speed nears the speed of the spokes, where the shutter can follow the spoke downwards as it moves. These conditions give birth to areas rather than lines. 
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