1. An image combining apparatus for generating a combined image by combining a plurality of images of an object sensed so that frames partially overlap each other, comprising: detection means for detecting an-image sensing condition upon sensing the plurality of images; storage means for storing the plurality of images, and the image sensing condition detected by said detection means in correspondence with the images; image combining means for generating a combined image by combining a series of images stored in said storage means, said image combining means having a plurality of combining means corresponding to individual image sensing conditions; and control means for controlling said image combining means to select one of said plurality of combining means on the basis of an image sensing condition corresponding to the series of images, wherein the combining means selected by said control means combines the series of images into a single image.