H versus resolution twinning test. The binned twinning-test calculations are shown for the Δ1–62NtNBCe1-A crystal and the full-length Nt crystal for twin operator 2 along a, b. As described in the text, the trends demonstrate that the calculated twin fractions are associated with hemihedral twinning and not NCS (green and red curves). In contrast, the binned twinning test for the full-length Nt crystal (purple curves) suggests little to no twinning despite an apparent twin-fraction calculation of 33.1% over the entire unbinned resolution range. Note that the Δ1-62NtNBCe1-A crystal before annealing has an apparent higher twin fraction of the crystal compared with that after annealing, either indicating a dramatic physical change in the lattice after annealing or a non-uniform crystal lattice.