An image taking apparatus having a first sensor configured to photoelectrically convert a subject image for outputting an image data, a second sensor configured to photoelectrically convert the subject image formed on the first sensor for outputting a photoelectric conversion signal, said second sensor having at least two photoelectric conversion areas that output the photoelectric conversion signal, an image processor configured to process the image data from the first sensor with a predetermined input and output characteristic, and a controller configured to set the input and output characteristic of the image processor based on dispersion information of a subject luminance distribution obtained from the photoelectric conversion signal from the second sensor.