A copying machine having a sorter and a finisher is capable of operating in three different modes: a copying mode with sorting, a copying mode without sorting, and a stapling finish mode. When the stapling finish mode is selected, an automatic magnification selecting mode (AMS mode) is automatically chosen, wherein only copies of one size are made during the copying operation such that unsatisfactory stapling caused by copy sheets of differing size is prevented. Also, if one of a number of sorting bins of the copying machine is not being used while the copying machine is operating in the stapling finish mode, a copying operation can be carried out in the copying mode without sorting, utilizing that bin.