Redshift-dependent (color-coded) calibration of the photometric error on the richness measurement (systematic shift μ_bkg, first panel, and statistical scatter σ_bkg, second panel), the strength of projection effects τ (third panel), the frequency of projection effects f_prj (fourth panel), the frequency of percolation effects f_msk (fifth panel), and the fractional increase in richness due to projection effects (last panel) as functions of richness as calibrated from simulations.