1. An image processing apparatus comprising: an exposure section for forming an image as a latent image on a film based on image data, and for exposing a partial area of the film for image formation with a predetermined exposure amount or with an output exposure amount calculated via a LUT with respect to a specified density; a development section for developing and visualizing the exposed film; a measuring section for measuring the density of the developed film; a density control section for controlling the exposure section and/or the development section so that the density of the next film to be image-formed will be optimized, based on a difference between a predetermined density value for comparison and the measured density value obtained through measuring a density of the partial area of the film by the measuring section; a time monitoring section for monitoring a down time when the power supply to the image processing apparatus is suspended; and a compensation section for correcting the control condition by the density control section, based on the down time monitored by the time monitoring section.