Mass fraction of the gas column density distribution reconstructed with a high pass filter (λ < 5 pc ) to the initial cloud mass (M_cl). This is done by performing an inverse Fourier transform on the Fourier transformed gas column density map of S1 (top), S2 (middle), and S3 (bottom) after removing signals from scales larger than 5 pc. The filled circle indicates the time at which the first sink particle is produced. The pronounced peaks in the lowest resolution runs of S1 and S2 indicate that the gas is slowly collapsing.