10.7554/eLife.23644.004Figure 1—figure supplement 2.Image processing of PLY rings.(A) Sample micrograph of amphipol-solubilized PLY rings picked for single-particle processing (red boxes). Scale bar: 50 nm. Class averages after 2D classification are shown on the right. (B) FSC curve for phase-randomized, masked map (red curve) indicates 4.5 Å resolution by the FSC0.143 criterion (red line). The sharp peak at 4.8 Å, reflecting the repeat distance between the 168 β-strands in the β-barrel, and a steep drop beyond that, indicating a resolution of 4.5 Å at the 0.143 theshold for the masked FSC, and of 4.6 Å at the 0.3 threshold for the map-vs-model FSC. The two values are in excellent agreement.DOI: http://dx.doi.org/10.7554/eLife.23644.004