Evaluating luminance values of a visual scene is of broad interest to accident reconstructionists, human factors professionals, and lighting experts. Currently, a common way to determine the actual luminance of an object is to locate the object on the subject roadway, at a substantially similar position, orientation and illuminance level and then measure the object with a luminance meter. This process can be extremely time consuming and could possibly require the roadway to be closed for safety purposes. Alternatively, the luminance can be calculated by measuring the reflectance of the subject surface and measuring the illuminance incident to the surface. After measuring the reflectance, it can then be used with any known illuminance to calculate the luminance of the object. This allows for an equivalently accurate measurement of luminance that is easier and quicker to make and could result in safer scene and vehicle inspections. This paper verifies that the luminance of a target at an incident location can be accurately and safely estimated using an off-site reflectance measurement, and on-site illuminance measurement at the incident location.