To provide an image processing system and others which can project an image more accurately and at higher speed while using a screen or the like as effectively as possible, there is provided a projector including a calibration image information generating section, an image projection section having a view angle adjusting section and a lens shift section for adjusting an optical axis of a projection lens to project the calibration image onto the screen or the like, a sensing section which senses a region including the projected calibration image and the screen or the like through a sensing surface to generate sensing information, a projection area information generating section which generates projection area information based on the sensing information, a target area information generating section which generates target area information based on the sensing information, and a projection control section which controls the view angle adjusting section and lens shift section based on the projection area information and the target area information.