Similar effects are also noted in the electron density of real crystal. 4.0 Global fold and some indication of secondary structure. 3.5 Secondary structure easily distinguished, large sidechains positioned 3.0 Most side chains are positioned, phi-psi angles are not well defined. Numerous water molecules are present in the model and the temperature factors are a reliable indication of disorder. 1.5 Backbone phi and psi angles are very well defined.
Hydrogens can appear in the structure.
Anisotropy can be detected in the temperature factors. 1.0 Hydrogens become apparent in the electron density map. In addition to smearing the electron density, the resolution of the data limits the refinement of the structure by limiting the number of observables. Consider measuring a data set to 2A resolution for a 70A cell. This would amount to measuring 8000 reflections, or data points.