On the basis of nXDS-determined orientation matrices, we calculated the electron beam-induced angular change in unit cell basis vectors for stationary crystals. From these, we could deduce the net rotation angle and axis of rotation best describing the coordinated changes in Bragg reflections as a function of dose. This analysis showed that the Cu(II)-serine crystal analyzed in Figure underwent a net 1.57 degree rotation over the course of 1.5 e -/Å 2 accumulated fluence. Such overall rotations were centered at apparently random axes, distinct from the basis vectors of the crystals' unit cells, and could be obscured by inflating the mosaicity estimate in nXDS. For example, frames in the dose series from the Cu(II)-serine crystal in Figure could be indexed enforcing high mosaicity, such that the beam-induced change in orientation matrix components and therefore net rotation of the crystal would appear negligible. As this outcome clearly does not match the reflection intensity changes measured for such a series, we enforced an initial mosaicity parameter that produced the best visual match between measured and predicted reflection locations, and kept this constant for all subsequent processing and analysis. Overall, the degree of correlated intensity fluctuations correlated with the degree of crystal reorientation as calculated by nXDS and this analysis method. The Zn(II)-histidine crystal analyzed in Figure ), for instance, only rotated 0.20 degrees after accumulating approximately the same fluence as the Cu(II)-serine crystal. Such observations led us to the conclusion that, at least within this substrate scope, beam-sensitive crystals of different compounds are prone to differing degrees of beaminduced lattice reorientation at both room and cryogenic temperatures.