PURPOSE: To easily dodge a printed image without test print even if its shape is complex by controlling a liquid crystal panel on an optical axis connecting a light source and a photographic printing paper while observing the liquid crystal panel on a monitor.

CONSTITUTION: When the image of a film 3 is printed on a photographic printing paper 2 with light from a light source 1, for instance, the image of the film 3 irradiated with the light for printing controlled in advance by exposure control is picked up by a TV camera 14. At this time, read image information is processed by a simulator 28, and the same image as that printed on the photographic printing paper 2 is displayed on the monitor 16. The position and a density of a dodged part are indicated by an indicator (light pen) 18 while the image on the monitor 16 is observed, density data is set based on the indication by a CPU 21, and a liquid crystal panel driving circuit 24 controls a liquid crystal panel 9 on an optical axis, based on the data. The image of the film 3, whose dodged part is changed in an exposure, can be displayed on the monitor 16, again, to confirm a dodging effect by a simulation.