1. A multi-imaging apparatus comprising: an image displaying memory for storing image data of an object acquired by a medical diagnostic appliance; a monitor means for displaying the image data of said image displaying memory; a window circuit having a plurality of window conditions, for windowing the image displayed by said monitor means; a memory disk for storing the image data of said image displaying memory; a camera unit for photographing the image displayed by said monitor in a portion of a multi-image film having a plurality of photographing areas; an input means for selectively inputting said window conditions and image identifying data; and a computer processor for selectively controlling a registermode in which the window condition data selected by said input means is registered in association with the image identifying data while said acquired data is stored into said memory disk, an window-condition displaying mode in which the window conditions based on said registered window condition data are automatically selected and said monitor means displays a correspondingly windowed image for photographing by said camera unit, a photographing mode in which the operation of said camera unit is controlled.