Pixels constituting the imaging element include at least four types of the determination pixels for which color filter patterns of adjacent pixels thereof are different from one another. At least one of pixels, which are adjacent to each determination pixel, is a first color pixel that has a color filter with a first color. Further, among the pixels which are adjacent to each determination pixel, a pixel, which is opposed to the first color pixel with the determination pixel interposed therebetween, has a color filter other than the color filter with the first color. Abnormal oblique incident light, which is incident into the imaging element, is detected on the basis of average values of the respective pixel data pieces corresponding to the types of these determination pixels.