In a camera in which a lens unit can be replaced, a camera, which individually grasps lens characteristics corresponding to a picked-up subject image, is provided. The camera is characterized by including a camera main body, a lens unit having an image pickup optical system for focusing a subject image, an image pickup means for picking up the subject image and converting it into electric image information, an optical characteristics memory unit for storing optical characteristics inherent to the image pickup optical system, an image memory unit for storing the image information and the optical characteristics of the lens unit used when the image information is obtained by causing them to correspond to each other, and an image processing means for subjecting the image information to image processing based on the optical characteristics which are caused to correspond to the image information.