Fourier shell correlation curves using known numbers of good and bad particles. “Good” and “bad” particles were identified from the intersection of the included and excluded particles, respectively, from the particle sets “by hand,” “highest ccc,” and “first good.” The mixtures of good and bad particles are such that the proportion of good particles was 100%, 90%, 75%, or 50%. Following the name of each particle set is the nominal resolution according to the 0.5 FSC criterion. (A) All 38,033 good particles were included with varying numbers of added bad particles. (B) A roughly constant number of total particles was included for each. Slices of three of these reconstructions are shown in Supplementary Figure 3.