An image pickup system includes an image pickup apparatus, and an information processing apparatus connectable with the image pickup apparatus. The image pickup apparatus includes an effective pixel area including a plurality of effective pixels configured to output accumulated electric charge as an image signal, a global reset circuit configured to output a global reset signal, and a reading timing generation circuit configured to temporarily stop and resume, at optional timings, reading of the electric charge accumulated by the effective pixels included in each of a plurality of divided areas. The information processing apparatus detects brightness of an object based on the image signals, and determines, based on the brightness detection signal, the number of the plurality of divided areas, a timing of reading the electric charge accumulated by the effective pixels included in each of the plurality of divided areas, and a timing of outputting the global reset signal.