Mass density field of mag1 galaxies (see Table 1). Upper panel: a slice of the whole data cube. The depth of the slice is 10 Mpc and the data are smoothed with a Gaussian kernel with a width of 0.7 Mpc. Lower panel: magnification of the area indicated with the square on the upper panel. For clarity, further spatial visualisations only use the smaller 50 × 50² Mpc area, as shown on the lower panel.