RV offset correction after fiber change as a function of FWHM (new observations have larger RV). Triangles are observed standard stars by LoCurto. The 60 sample stars with observations pre and post fiber change are coloured in blue, red or green circles (with their mean FWHM pre fiber change and after correcting from focus drift) and extrapolated using polynomials of 1 st, 2nd or 3rd order fitting the standard stars, respectively.