Distribution of the outputs of the nuller during the observation of a binary object (companion of contrast c = 10⁻² at (+4.8, +1.8) mas) in the presence of 50 nm RMS residual piston excursions drawn from a normal distribution. From left to right: the nuller alone, the nuller+sensor and the kernels. The dashed lines mark the expected location of the different nulls (and their kernels) in the absence of piston excursion.