Comparison between the Herschel SPIRE 500 μm flux density and the Planck 545 GHz flux density for the 43 PCCS sources with a clear counterpart. The Herschel flux densities have been converted to correspond to a wavelength of 550 μm (see text). The different panels correspond to four different methods used in the PCCS to measure flux densities. The solid green line represents a linear regression fit to the data, the solid blue line corresponds to a one-to-one correlation. The GAUFLUX panel only contains 33 sources as this flux density estimate is not provided for all sources in the PCCS.