application_number US 3519102 A description hereinafter a preferred embodiment of the present invention will be explained referring to the accompanying drawing fig1 shows an embodiment of the present invention and depicts a schematic laboratory system for reproducing image data obtained by a digital camera in the form of a print or the like a digital camera 1 comprises as does a conventional digital camera an image pickup unit 4 such as an optical system for carrying out recording and an ae processing unit 5 for carrying out automatic exposure processing a function such as automatic focusing is meant to be included in the image pickup unit 4 however the presence or absence of such a function or a level thereof varies depending on the type of digital camera the digital camera 1 of the present invention further comprises a recording information adding unit 6 the recording information adding unit 6 is used to add a variety of recording information to digital image data obtained by recording the information to be added is as listed below for example first the u03b3 property representing a ratio of output voltage to an input light amount is listed as information specific to a camera the u03b3 property affects contrast of a picture and often varies between cameras with a high price and a low price as information specific to a camera other than the u03b3 property a focal length and f value of a lens can be listed it is also preferable to add the content of ae processing carried out by a camera as the recording information as ae processing which is generally carried out average processing peak.