A method for calibrating a radiation detection medium by exposing arbitrary locations of a radiation detection medium to a plurality of known radiation dose levels is described. One particular aspect of the method includes the steps of automatically determining the location of each arbitrary exposed location, measuring the density of each of the arbitrary exposed locations, matching each measurement for the arbitrary exposed locations with the corresponding radiation dose level thereby generating an array of paired data values for radiation dose level and measured density and calculating a calibration based on the array of paired data values.