Chloroplast motion under dim light conditions

Elodea densa was kept in an aquatic culture. Ambient light conditions were applied 1h before image acquisition. Imaging preparation: a low-light adapted leaf was detached and placed between two glass slides. Lower cell layer is displayed. Microscopy: Bright field microscopy was performed with a Nikon TI2 microscope using a halogen light source and a red-light 620nm cut-on wavelength filter at low light intensities of 7.2 W/cm^2 in combination with a Photometrics BSI Express sCMOS camera with high quantum yield to enable imaging every 1s with a $63\times$ water-immersion objective (NA=1.2) and pixel resolution of 0.1µm/px. Description: Chloroplast.zip: Contains ome.tiff files for 3600 frames of chloroplast motion (total duration 1h) The dense chloroplasts (dark circular objects) inside the plant cells move by actin-mediated propulsion mechanism. 211013_CP_rawLabelMeasures.csv: Analysis of segmented data (3600 frames) 211013_CP_tracks_vel.csv: Trajectories (with velocities) constructed by trackpy from center-of-mass positions of the 211013_CP_rawLabelMeasures.csv. Velocities where calculated using the first derivative of 3rd order Savitzky-Golay filtered data (Kernel width 11s).