Figure 3.
Improved resolution and map quality using beam-tilt refinement. (a) Strategy for grouping micrographs. Micrographs were grouped into 25 groups (5 × 5), 100 groups (10 × 10) and 400 groups (20 × 20). (b) The effect of group size on beam-tilt refinement and subsequent resolution estimation for refined 3D structures. (c) Sharpened 3D reconstruction for particles placed into 400 micrograph groups filtered to 3.8 Å resolution. (d) FSC curves for 3D reconstruction in (c). (e) Beam-tilt measurements for each group displayed with respect to microscope beam-image shift for X coordinates (black) and Y coordinates (gray). Dashed lines show least-squares fit where R 2 = 0.96 (beam tilt X) and R 2 = 0.64 (beam tilt Y).