In case study 2, the image processing workflow also follows that shown schematically in figure , but with an additional image registration step to align the data acquired at different SoC. Projections were processed and reconstructed using Savu data pipelines at the I13-2 beamline . Projections were processed with darkflat field correction and the ring removal algorithm from Vo et al. and were reconstructed with TomoPy's GridRec algorithm . The reconstruction was computed with limited angles (3-177 • ) because of projections at extreme angles being obscured by the sample holder. The reconstructed data was cropped to contain the ROI only. This data was registered such that corresponding pixels represented the same real space in tomograms taken at different SoC. This was achieved using the SimpleITK python library . This registered data was converted to 8-bit unsigned integer volumes and smoothed using the fast non-local means (NLM) algorithm from scikit-image which was parallelised using the python concurrent.futures module . A threshold was used to calculate a binary segmentation of solid and void. Morphological binary erosion and dilation was required to fill binary 'holes' and remove 'islands' from the binary segmentations. When calculating the labels segmentation, it was critical to preserve particle labels between time steps so that they could be tracked at different SoC. The same watershed segmentation using a smoothed distance map (as in case study 1) is used to compute the label segmentation in the pristine state. However, for the remaining tomograms (acquired at different SoC), the label values are initiated using seeds labelled with the corresponding value from the pristine labels segmentation. This enforces the same labels across the tomograms but relies on good registration between the tomograms and relatively little particle drift during the experiment. The unsmoothed 8-bit unsigned integer grey-level data and the labels segmentation was then used in the GRAPES analysis (figure shows example segmentations).