1. A method performed by an image processing apparatus, comprising: scanning a color matrix film with visible light to generate a digital color copy thereof; scanning the color matrix film with infrared light to generate an infrared alpha layer image thereof; separating a color grid of the color matrix film from an underlying silver layer of the color matrix film to produce a color grid image, wherein separating the color grid from the underlying silver layer includes computationally dividing the digital color copy of the image by the infrared alpha layer image; and using the color grid image to generate an altered version of the digital color copy.