Figure 3.

Diffraction data-quality parameters as a function of dose for five insulin crystals measured at room temperature, showing clear manifestations of radiation damage. (a) The decay of the mean intensities of the whole data sets, (b) the I/σ(I) ratio for reflections in the high-resolution shell 2.4–1.9 Å (normalized to the value of the first subset), and the increase in (c) the relative B factors and (d) the scaling factors, as defined by equation (3), are all plotted as a function of absorbed dose. The solid lines in part (a) correspond to an exponential fit as given by equation (2), while the lines in parts (b)–(d) are meant as a guide to the eye.