Diagram illustrating the effect of multi-resolution observations on the interpretation of Faraday complexity. The black circle indicates a linearly polarised, synchrotron-emitting source, spatially unresolved in A, B and C. The white ellipse indicates the angular resolution of the observations, and the vertical arrows indicate the maximum angular scale of the observations. The blue-shaded regions are the polarised emitting foreground, with emission at smaller scales in panel C, and the yellow-shaded region is a turbulent foreground screen. The dashed arrows show the paths of emission from the various sources, and the number of observed Faraday components is indicated in the top right corner.