*Dragonfly* reconstruction parameters for all data sets except for the schedule of the deterministic annealing parameter $\beta$. A low value of $\beta$ was not necessary when the signal level was low since this parameter acts to solve convergence issues for very high signals by broadening the PDOs. Appendix A contains details of the parameters for each subset. The 3D intensities from *Dragonfly* were phased with identical parameters in every case to generate electron densities. Each reduced data set was split into two halves and independently reconstructed in order to calculate the “gold-standard" FSC and CC$_{1/2}$, and this whole process was repeated 10 times to obtain error bars on the metrics.

The results of reducing signal strength are summarized in Fig. \[fig:split\_metrics\]. In Fig. \[fig:split\_metrics\](a) we plot one metric, CC$_{1/2}$, as a function of $q$ for both the full data set and a selection fraction of $p=2^{-8}=1/256$. Fig. \[fig:split\_metrics\](a) shows that the reconstruction from the reduced data shows a slightly decreased quality metric compared to the full data set.

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   ![Dependency of reconstruction metrics on selection fraction. (a) Plots of CC$_{1/2}$ vs $q$ for the full data set and for a selection fraction of $p=2^{-8}=1/256$. Error bars represent the standard 