- The equations relation cross-correlation coefficient to signal-to-noise ratio on slide 7 of the PEET Fourier Shell Correlation presentation are incorrect. The correct relations are:

and$$CCC^2\; =\; \backslash frac\{SNR\}\{(1\; +\; SNR)\}$$

Signal-to-noise ratio is expressed here as a ratio of energies. Use the square root of this expression if the ratio of root-mean-square amplitudes is desired.