Reconstruction Error between original images and their PCA projection. Top panel: reconstruction error for fixed dimensionality reduction onto the 60 (215) dimensional space in two (three) dimensions. The dashed line represents the 90% quantile. We observe that 90% of all images have a reconstruction error less than 0.022 (0.027). Bottom panel: 90th percentile of the reconstruction error as a function of the number of eigengalaxies used for reconstruction. The reconstruction error is a strong function of eigengalaxies, and already 15 (60) eigen-galaxies lead to a reconstruction error better than 5% in 2D (3D).