Hi, I am using phenix.refine_dev_282 for a rigid body refinement. The output pdb file is exactly the same as the input model even though there are obviously some large movements. Here are some information from the log file. Information about total rigid body shift of selected groups: rotation (deg) translation (A) xyz total xyz total group 1: 0.051 -5.493 -1.073 5.60 0.55 -3.15 -1.35 3.47 group 2: 0.254 0.562 0.252 0.67 0.36 -3.99 0.87 4.10 group 3: 3.807 4.001 -2.262 5.92 -0.81 -3.17 1.06 3.44 group 4: 2.275 -4.215 1.909 5.12 -0.18 -2.95 -1.43 3.28 group 5: -1.902 -5.750 -3.206 6.81 -1.99 -4.44 0.27 4.88 group 6: -4.932 -3.939 -5.340 8.16 -0.18 -2.08 -0.25 2.11 group 7: -1.140 -0.769 -7.715 7.83 0.73 -2.91 0.04 3.00 group 8: 2.008 -1.858 -1.236 3.02 -1.10 -5.44 -0.82 5.61 But then the model didn't change at all. stage Deviation of refined model from start model max min mean 0 : 0.000 0.000 0.000 1_bss: 0.000 0.000 0.000 1_rbr: 0.000 0.000 0.000 1_bss: 0.000 0.000 0.000 1_adp: 0.000 0.000 0.000 1_bss: 0.000 0.000 0.000 Is this a bug? -- Jianghai