Comparison of magnetic field inclination from ME inversion (γ_inv) and from NLFFF extrapolation (γ_ext) within the outermost ellipse marked in Fig. 1. From left to right, the first and second panels show the scatter plots of γ_inv and γ_ext, respectively, as a function of radial distance from the spot centre for data from 22:00 UT (fully fledge spot). The third panel shows the probability density function of the relation between γ_ext on γ_inv for all times and all pixels within the ellipse. The green colour corresponds to pixels with I/I_c < 0.5 (umbra), the magenta colour corresponds to pixels with 0.5 < I/I_c < 0.95 (penumbra), and the red colour corresponds to pixels with I/I_c > 0.95. The right-most panel shows the mean difference between the inclination values determined from extrapolations and from inversions in penumbral regions (magenta line) and umbral regions (green line). The black line shows the smoothed value for all pixels within the sunspot.