An exchangeable lens detachably mounted at a camera body includes: an optical characteristics storage unit; an optical characteristics information generation unit; and an optical characteristics transmission unit. Peripheral shading information for only some image heights is stored as the information pertaining to the peripheral shading characteristics of the exchangeable lens into the optical characteristics storage unit, but peripheral shading information for at least one image height position among five image height positions equivalent to integral multiples of y1, which represents an image height equal to ⅙ of an image height measured from a center of a substantially rectangular image capturing range to one of four corners of the image capturing range, obtained by multiplying y1 by integers in a range 2 through 6, is not stored in the optical characteristics storage unit.