An image capturing apparatus which captures an image of a subject with an image sensor having pixels each including a plurality of areas and generates a RAW image for each of the plurality of areas from a signal generated by the image sensor. The apparatus generates a first RAW image and a second RAW image from the RAW images, generates first image data by performing first development on the first RAW image, generates first RAW image data and second RAW image data by compressing the first RAW image and the second RAW image and performs second development on the first RAW image having a higher processing load than the first development. Second image data is generated by the second development on the first RAW image by using the second RAW image.