a color meter for measuring the respective intensity of the blue , green and red regions of an illuminating light source to provide the photographic information according to the measured value . the present invention provides an appliance , which directly provides , as the final output , the light balancing factor or the color compensating factor according to the necessary one from among the measured informations of the light intensity of each region of blue , green , red and an information determined according to using film , video image pickup tube , solid image pickup element , etc . and of which the operation is simple and the correcting filter can be simply and quickly determined .