Fig. 5

Multi interval tracking. The video had to be split into several intervals due to faltering focus. a Time course of contrast, SD2 of each video frame; normalized by the maximal value. Blue dashed line marks the warning threshold, 5% drop from the maximum. b Tracking was divided into four intervals. The peak marked by the label (I) is a result of separation of pipette and the bead, as shown in panel C-I. Intervals of measured deformation marked in green and labelled (II) are mutually compatible, using the same pipette pattern shown in panel C-II and the same reference distance x ₀ — the force calibration is identical. The focus during the interval of data in cyan, labelled (III), was locally stable, and could be tracked using local pipette pattern, before the focus reverted to the original state; the pipette pattern is shown at the panel C-III, clearly different from the pattern C-II. The calibration of the cyan interval was set manually to correspond to the final values of preceding interval. Total computational CPU time 432 s. The video file used for this analysis, multiinterval.avi, is included in the program repository