Figure 4.

The CI for an electron density map. The map was computed for lysozyme measured to 1.54 Å resolution, using observed structure factor amplitudes and (a) phases obtained using anomalous dispersion from intrinsic sulphur atoms (red curve), (b) phases subsequently improved by density modification (blue curve) and (c) phases computed from the refined, final model (purple curve). The correlation coefficient to the map corresponding to the final model is 0.51, 0.81 and 1.0, respectively. (d) Distribution of the local value of the CI, computed from all non-negative density values within a sphere of 3 Å radius centred at each grid point of the map.