A computer system method includes determining a first surface illumination on an object based upon a respective irradiance, determining a first surface reflection based upon the respective irradiance, determining a second surface illumination on the object based upon a respective irradiance, determining a second surface reflection based upon the respective irradiance, receiving a first weighting for the first illumination and the first reflection value, and a second weighting for the second illumination and the second reflection value, wherein the weightings are different, determining a first surface illumination in response to the first illumination value, the first reflection, and the first weighting, determining a second surface illumination in response to the second illumination value, the second reflection, and the second weighting, and determining an image including the object based on the first surface illumination and the second surface illumination.