A printing system is provided that dynamically adjusts the method of printing an image based on the lightness or darkness of the medium upon which the image will be printed. The reflectivity of the medium upon which an image is to be printed is determined, and the way in which the image will be printed is adjusted based on the determined reflectivity of the medium. For lighter colored mediums, on which sufficient contrast will be provided, the image can be printed directly onto the medium. For darker colored mediums, on which the ink used to print the image will not provide enough contrast with respect to the medium to produce a reliably readable image, the method of printing the image is modified to ensure that sufficient contrast is always provided to produce a reliably readable image.