Modeled reflectance maps of the lunar surface observed at (a) i = 30°, e = 0°, and g = 30° and (b) i = 60°, e = 0°, and g = 60° derived using an empirical photometric function (Equation (2)) and the dense WAC photometric library (e.g., Figure 6). (c) Phase angle ratio image created by dividing (a) by (b). Each map spans 0° to 360° in longitude and ±30° in latitude with graticules set at 15° intervals.