Edges are crucial descriptors for image analysis and rely mostly on local spectral distances. In this paper, local spectral changes are assimilated to the local statistical dependences which are measured by the local mutual information. This metric is shown to be invariant to unknown bijective transforms which makes it a good candidate for analyzing consistently satellite images which are affected by uncontrolled spectral distortions. Such an edge property is assessed with WorldView-2 multi-angular sequence of images, where spectral distortions arise with far nadir view angles.