1. A method for creating a reflectance characterization matrix, the method comprising:illuminating training reflectances by producing a series of colored flashes by sequentially illuminating each color channel of a multi-channel light source;
causing a series of images to be captured by a multi-channel image sensor in conjunction with the series of colored flashes;
calculating a training fingerprint for each pixel of each image of the series of images;
setting up linear regression using the training fingerprints and the training reflectances; and
forming a reflectance characterization matrix by performing multiple linear regression for each wavelength within a predetermined spectrum.