Fitted parameters for the target halfway between the sub-spacecraft points (green diamond in Fig. 2) assuming ϕ_h = 0. Results for each radial order n are connected by lines (see legend in top panel). In the middle panel the fitted c_t values are divided by c_t,ref for ease of display. Black lines indicate the results with the nominal time shift and image offsets. Red lines show the fits resulting from an arbitrary additional shift of 2 s between the instruments. Green and blue lines show the results obtained by shifting the SO/PHI data relative to the HMI data by an additional 1.0 remapped pixel in the fitted cubes (0.08°). The green lines use a shift in the direction of the maximum phase difference, the blue in the orthogonal direction. In the middle panel the magenta lines show the results for a shift in the opposite direction (i.e., by −1.0 pixels vs. +1.0 pixels for the green lines). The black lines are plotted last, and hence the other colors are often invisible. To avoid poor fits, only modes with l ≥ 200, k≤ 0.9 times the Nyquist frequency for SO/PHI (l ≈ 620) and 1.5 mHz ≤ν ≤ 5.0 mHz are shown. The smooth red curves show c_t,ad.