Excitation error (Sg)-dependent effects of the image tilt induced parabolic and elliptical distortions on the position of a reflection, with the distance from the centre of the distortions equal to 1.5 Å−1 and with the amplitudes of the induced distortions the same as those found experimentally for the PED experiment DS8. For the sake of clarity, the phases of the distortions are set exactly to 0° so the radial components cause only reflection shifts and the tangential components cause only reflection splitting. The left-hand column shows the shift effects of the radial components of (a) the parabolic distortion, (c) the elliptical distortion and (e) their combination. Similarly, the right-hand column shows the splitting effects of the tangential parts of (b) the parabolic distortion, (d) the elliptical distortion and (f) their combination. Blue lines correspond to phases of the precessed electron beam between 0 and π, red lines correspond to phases between −π and 0, and purple lines correspond to phases between −π and π.