Correlations of the VIS2 for the GRAVITY science camera, extracted from a single P2VM-reduced file (upper left panel) and our one-parameter model fitted to them (upper right panel). The bottom panels show the corresponding covariances obtained by multiplying the correlation C_ij with the product of the standard deviations σ_iσ_j. Correlations/covariances within the same baseline are highlighted with red squares and correlations/covariances between baselines having a telescope in common are highlighted with orange squares.