1. A system for determining image intensity of a radiograph, comprising: an illuminator for providing lighting to the radiograph; an image reference standard having a predetermined color; a digital imaging device for obtaining a digital image of the radiograph and the image reference standard; a computer for receiving and storing the digital image and for executing programs; and an image analysis program being executed on the computer for providing from the digital image a first image intensity value of a target area in the radiograph and a second image intensity value of the image reference standard and for computing a normalized image intensity value of the target area using the first and second image intensity values.