Once the sensor has captured the light from the subject and generated a charge, the data has to be transferred in a readable form to the camera’s processor as quickly and as accurately as possible, and there are different ways of achieving this.
The original method, which gave the CCD (charge-coupled device) its name, relies on reading out the charges row by row, linking the end of one row to the beginning of the next. In this way, the charges are “coupled.”
One of the key issues is the speed at which the image data can be moved off the sensor so that it is ready for the next exposure. This decides the shooting speed—an important factor for sports and news photographers in particular—and the baseline that most professionals ...