Figure 5.

Cross correlations for 3 ms dwell time images using DPC (top) and zinc fluorescence (bottom). Not only is the cross correlation peak for DPC narrower (as shown with the FWHM marker lines), it is also free of the noise fluctuations present in the zinc fluorescence cross correlation. This makes the DPC signal clearly superior for robust projection alignment, even when low-dose individual fluorescence projections are acquired as part of exploiting dose fractionation (Hegerl & Hoppe, 1976 ▶).