1. An image processing apparatus, comprising: an imaging unit that is configured to acquire a plurality of images with different exposure times; a position offset detection unit that is configured to detect a position offset between a plurality of images filmed by the imaging unit; a combining ratio calculation unit that is configured to calculate a combining ratio in case of combining the plurality of images based on pixel values of at least one image among the plurality of images filmed by the imaging unit and the amount of the position offset detected by the position offset detection unit; and an image combining unit that is configured to combine the plurality of images based on the combining ratio calculated by the combining ratio calculation unit.