Imaging device, imaging device body, and lens barrel

An imaging device body comprising:

• a lens barrel mounting portion on which a lens barrel including a focus lens and a diaphragm disposed on a light path and an apodization filter to be inserted/retreated onto/from the light path is detachably mounted;
• an imaging element that photoelectrically converts an incident ray emitted from an imaging region of the lens barrel and outputs an imaging signal;
• a distance-information acquisition unit that acquires information about a distance to a subject in each focus detection region by setting a plurality of focus detection regions in the imaging region in a state in which the apodization filter is retreated from the light path and performing focus detection on the basis of the imaging signal while moving the focus lens;
• a depth-of-field calculating unit that calculates the depth of field for one major subject on the basis of the information about a distance to the major subject, which is selected from the plurality of subjects, and a diaphragm value of the diaphragm that is corrected on the basis of optical characteristics of the apodization filter;
• and
• an insertion/retreat control unit that determines whether or not a subject other than the major subject is present outside the depth of field on the basis of the information about the distance and inserts the apodization filter onto the light path in a case in which the subject other than the major subject is present outside the depth of field.