Structure of hepatitis B virus capsid determined at 100 keV. (a) Typical micrograph after motion correction. Contrast is adjusted to ±3σ from the mean intensity. (b) 2D class averages. (c) Sharpened masked 3D reconstruction of hepatitis B virus capsid from N = 132 particles with icosahedral (I) symmetry. (d) Gold-standard FSC plot corresponding to the calculated map, showing the correlation between the phase-randomized (yellow), unmasked (blue) and masked (red) half-maps. The plot terminates at the Nyquist frequency. (e) Orientation distribution of the hepatitis B capsids contributing to the final reconstruction (Mollweide projection). All Euler angles are assigned within one asymmetric subunit for the icosahedrally (I) symmetric particle. The colour scale (linear) corresponds to the normalized density of views (blue, low; red, high). E = 0.8 is the efficiency of the orientation distribution, indicating nearly uniform sampling of the particle views.