Image capture and processing. The image capture was made using a REDMI Note 10s smartphone built-in camera. The settings were configured using the manual mode adjusting the white balance to cloudy mode, focus to 1.79 mm, shutter speed in 1/200 seconds, and ISO 80. For short distance captures the Macro lens was used with a resolution of 2 megapixels. For dynamic experiments, the time-lapse function was used, capturing pictures every 5 seconds for 600 seconds. An ad-hoc Plexiglas ® cell (Figure SI 1) was designed using Corel Draw software, and fabricated using an Epilog Mini Laser Engraver, equipped with a 30 W CO2 laser (85% power, 15% speed). In addition, an adhoc stand made of black plexiglass was used to isolate the device from ambient light and to set the capture distance between the camera and the beads to 35mm. Back illumination was obtained using a USB-powered LED light bar (Extreme Tech). The free software ImageJ 56 1.51q was used for the edition and processing of the images. Both still and time-lapse images were processed as stacks using the same procedure, to increase the reproducibility. The region of interest (ROI) selected in each capture was set as the circular area of each individual bead. Size distribution studies were performed by measuring the diameter of the different beads in those pictures, using the Set Scale function calibrated scale as a reference.