Power spectral density of the 2018 November 9 PSP data interval (left) and of the 2007 January 20 C3 data sample (right). Vertical lines indicate frequencies associated with the ion inertial length (red) and the ion gyroradius (green). The blue lines indicate the smallest scales considered in the analysis. The typical slopes in the inertial and kinetic ranges are reported for reference (dotted lines).