Hi Ed, > If nothing else works, can I change this factor with: > real_space_refinement { > mode = simple *diff_map > target_map_name = 2mFo-DFc > model_map_name = Fc > grid_resolution_factor = 1./4 > > ? Or its hard-wired for all three maps? yes, you can change to 1./3 and this should reduce the map size. Pavel.