A: space-time map corresponding to observation at μ = 0.4. This map is generated by plotting the continuum intensity profile along the horizontal axis, obtained from each Stokes I images (of 148 total frames) along the spectrograph slit. Each profile was obtained at 6.7 s, so that the whole measurement shows a temporal evolution of the FOV of the spectrograph slit of 16.5 min. B: normalized continuum intensity profile, obtained by averaged over 1.78 min from observation beginning. The corresponding time interval is indicated between the red horizontal lines in the space-time map. This profile is used as a parameter to indicate the granular and intergranular regions in Fig. 5. C: space-time map corresponding to observation at μ = 0.8. D: normalized continuum intensity profile. This was obtained by averaging over 6.98 min from the beginning of the observation (the corresponding time interval is indicated between red horizontal lines in the space-time map).