A solid-state image pickup apparatus includes an image sensor provided with an image sensing surface including a photosensitive zone for measurement and an optical black area adjoining an output circuit. Signal charges read out from the photosensitive zone for measurement and optical black area are used to calculate local horizontal transfer efficiency in the event of concentration of signal charges transferred from a horizontal transfer path to the output circuit. Image signals read out from the photosensitive zone for measurement and the optical black area, which are remote from the output circuit, are used to calculate an all-stage horizontal transfer efficiency over all stages of the horizontal transfer path. The horizontal transfer efficiencies are used to calculate stage-based horizontal transfer efficiencies at consecutive positions on the horizontal transfer path. The stage-based horizontal transfer efficiencies are used to calculate-transfer efficiency correction amounts for the consecutive positions in the horizontal direction.