Predicted fringe contrast when observing a binary star with equal fluxes and a separation of about 10 mas with the four UTs and a fringe sensor working in the H-band. The left panel shows the (u,v) tracks overlaid on the fringe contrast from the model. The right panel shows the fringe contrast versus time for 4 h for each baseline. The figures were made with the aspro public software from JMMC.