Raw transmission maps of the differential null for three different input orders and the same sky pointing, on the meridian for a target at Dec –50.0. The signal is summed over all spectral channels. Unlike the four-telescope kernel-nuller, NOTT can only obtain one at a time. The values take into account the transmission of the whole instrument, (including quantum efficiency etc.) and are given in units of étendue [sr.m²], interpreted as the equivalent collecting capacity with regard to each elementary patch of sky (pixel).