File Name : si_0_referees.eps

Caption : si fig 1. particle orientation change after they contact the interface. particles obtain a stable orientation angle no matter on the oil viscosity. we fit our experimental data to gaussian distributions. all of them are compatible with a mean value of -6±10º indicating no clear preference for the particle to point into or away from the oil phase. since data for 5cst could seem left-skewed, we also fitted it to a skewed normal distribution. value of the shape parameter is α=0.25, and therefore we do think that still is compatible with a normal distribution.