Figure 4. Three-D chair views showing an inline vertical slice through (a) most-negative amplitude curvature (long-wavelength), (b) most-negative structural curvature (long wavelength), (c) most-negative amplitude curvature (short-wavelength) and (d) most-negative structural curvature (short-wavelength). Notice the higher level of detail on amplitude-curvature displays (a and c) compared with that on structural-curvature displays (b and d).