An image processing apparatus comprising: obtaining means configured for obtaining an image signal that is capable of generating a plurality of reconstruction images, wherein each of a plurality of subjects included in the image signal having different subject distances is capable of being focused in each reconstruction image; generating means configured for generating reconstruction images from the image signal obtained by the obtaining means; determining means configured for determining a subject distance to be focused in each of the reconstruction images to be generated by the generating means; receiving means (101, 110, 112) configured for receiving an instruction related to enlarged display of a region of one of the reconstruction images, and an instruction related to reduced display of an enlarged one of the reconstruction images that is displayed; and display control means configured for causing a displaying medium to display the one of the reconstruction images generated by the generating means, characterized in that the determining means determines a subject distance of the one of the reconstruction images to be generated: as a subject distance in which a subject in a region where enlarged display is to be performed is focused in a case where the instruction related to enlarged display is received, and as a subject distance that is the same as the subject distance that is determined with regard to one of the reconstruction images displayed on the displaying medium before enlarged display or as a subject distance that is the same as the subject distance that is currently displayed on the displaying medium, in a case where the instruction related to reduced display is received; wherein the determining means switches, based on a setting of the image processing apparatus, a determination method of a subject distance in the case where the instruction related to reduced display is received, and the display control means causes the displaying medium to display the one of the reconstruction images generated by the generating means based on the subject distance that is determined by the determining means. obtaining means configured for obtaining an image signal that is capable of generating a plurality of reconstruction images, wherein each of a plurality of subjects included in the image signal having different subject distances is capable of being focused in each reconstruction image; generating means configured for generating reconstruction images from the image signal obtained by the obtaining means; determining means configured for determining a subject distance to be focused in each of the reconstruction images to be generated by the generating means; receiving means (101, 110, 112) configured for receiving an instruction related to enlarged display of a region of one of the reconstruction images, and an instruction related to reduced display of an enlarged one of the reconstruction images that is displayed; and display control means configured for causing a displaying medium to display the one of the reconstruction images generated by the generating means, characterized in that the determining means determines a subject distance of the one of the reconstruction images to be generated: as a subject distance in which a subject in a region where enlarged display is to be performed is focused in a case where the instruction related to enlarged display is received, and as a subject distance that is the same as the subject distance that is determined with regard to one of the reconstruction images displayed on the displaying medium before enlarged display or as a subject distance that is the same as the subject distance that is currently displayed on the displaying medium, in a case where the instruction related to reduced display is received; as a subject distance in which a subject in a region where enlarged display is to be performed is focused in a case where the instruction related to enlarged display is received, and as a subject distance that is the same as the subject distance that is determined with regard to one of the reconstruction images displayed on the displaying medium before enlarged display or as a subject distance that is the same as the subject distance that is currently displayed on the displaying medium, in a case where the instruction related to reduced display is received; wherein the determining means switches, based on a setting of the image processing apparatus, a determination method of a subject distance in the case where the instruction related to reduced display is received, and the display control means causes the displaying medium to display the one of the reconstruction images generated by the generating means based on the subject distance that is determined by the determining means.