PURPOSE: To improve operating efficiency, by a method wherein a blank typing photocomposing characters are arranged at regular intervals within the printing range, and the faulty blank typing photocomposing characters are corrected, added or eliminated previous to the real photocomposing thereof, after that, they are arranged again at regular intervals within the printing range.

CONSTITUTION: When the arranged blank typing photocomposing character 'V' is incorrect, the correction thereof to the character 'I' is carried out by a method wherein; a blank typing switch in a command input division 31 is pushed to make a mode for blank typing again; after a cursor 30, displayed on the scope of a monitor display 1, is moved to the position on the character 'B', a cursor lock switch is pushed; pushing a blind typing correction switch leads the scope of the monitor display 1 to be moved to display the character 'V' and a cursor 30 on the position of a character window 28; successively, a character 'I' is selected from a character plate 37; cut of a shutter 44 results in elimination of the character 'V', and alternatively display of the character 'I' of semi-brightness; simultaneously, a simbol '-' and a character 'III' which were positioned next to 'V' are respectively come close to 'I' by the width's difference between the characters 'V' and 'I'. Accordingly, it is made possible to dispense with the trouble of starting again from the beginning caused from the photocomposing error.