Procedure for the estimation of the contrast curve, the orange star corresponds to the linear interpolation, the black star to the corresponding TPR, the blue stars to the two previous estimations used for the linear interpolation and the green star to the flux corresponding to a TPR of 0.5. The red curve makes the link between the flux and the true positive rate in the case of a single false positive while the green line shows the tolerance’s interval of [0.45,0.55].