An imaging apparatus having a solid-state image sensor, such as a CCD, accumulates information charges corresponding to an image of an object and generates an image signal using the stored charges. A driver provides clock signals to the sensor which define vertical and horizontal scan periods, so that the information charges are accumulated in a predetermined exposure period, in accordance with a timing signal. A first exposure information generating circuit determines whether a level of the image signal is within an appropriate range and produces first exposure information based on the determination results. A second exposure information generating circuit calculates second exposure information using the image signal. A selector selects the first exposure information when the level of the image signal is outside of the predetermined exposure period and selects the second exposure information when the image signal is within the predetermined exposure period. A timing control circuit receives the selected exposure information from the selector and generates the timing signal.