Deflection field (x component) from a simulation of ψDM with λ = 10 pc. The top panel shows the original simulated deflection field. The middle panel illustrates the Gaussian decomposition of this field at 50 times the resolution and obtained with 500 Gaussian functions. The bottom panel represents the difference, which is at the percent level. We used the Gaussian decomposition to interpolate the deflection field to much higher resolutions. The Gaussian decomposition for the y component of the deflection field looks similar.