Estimates were made of the efficiency with which color spaces code color information from images of natural scenes. Six spaces were tested, namely, CIE XYZ tristimulus space, and the spaces CIELUV, CIELAB, CIELAB and S-CIELAB after chromatic adaptation with CMCCAT2000, and the space CIECAM02. For each space, the information available and the information retrieved in color matching were calculated for images of 50 natural scenes under different daylight illuminants. The information available was decomposed into components associated with the individual variables of the space and the interactions between them, including redundancy and illuminant-dependence. It was found that the information retrieved was much less than the information available, and that its decomposition depended on the space. The differing efficiencies of the spaces were interpreted in relation to the effectiveness of opponent-color and chromatic-adaptation transformations, and the statistics of images of natural scenes.