Nuller output transmission maps of a kernel-nuller at the focus of the four VLTI UTs, observing a ±15 mas FOV surrounding the target HIP 107773. The figure shows the maps of the six nuller outputs for a pointing exactly at zenith. We see that these maps differ from one another and this diversity in the output response provides a constraint on the properties of a potential companion in the vicinity of a much brighter star. A white star in each map marks the location of the central star where the transmission for all channels is equal to zero, by design. About the centre of the field, the maps are asymmetrical. For transmission maps, this asymmetry is a desirable trait as it allows for the elimination of centro-symmetric astrophysical features that would otherwise hide a planetary companion. With four input beams being split into six outputs, we expect an average planet flux of 4/6 (=0.66) per channel. All six maps share the same colour scale where the transmission peaks at approximately two times the planet flux collected by a single aperture.