Completeness test. The plot shows the completeness fraction as a function of the g′₀ magnitude for the artificial stars added in the three filters inside a galactocentric radius of 5 × r_eff (black line), for the artificial stars inside the rectangular region used to estimate the background contamination (green line), and inside the region between NGC 4709 and NGC 4696 (red line) represented by the red rectangle in Fig. 3. The dashed lines show the 50% completeness limit.