Light reflection and light transmission of two paper substrates and model prints printed on these materials by inkjet and electrophotographic methods are investigated. For this purpose, we have used optical scanning of the given objects placed in series on a black substrate, effectively absorbing light radiation, and on a metal mirror. The objects were scanned using an available flatbed office scanner. The obtained experimental data on reflection, transmission, scattering and absorption of light in tens of thousands of irradiated sample points were processed in a computer program Scilab-5.3.3, which allowed to determine the average parameter values of the optical properties of these objects and the characteristics of their heterogeneityin a short time. As a result, the advantages of the computerized method of scanning printing materials and products over the widely used reflectometry method have been convincingly demonstrated, the method’s prospects for solving the problem of improving the printing quality have been confirmed. In comparison with all other known methods for controlling the printed products, the optical scanning method is the most informative, accurate and universal.