SPHERE observations of LkHα 330. Left panel: Q_∅ of the H-band observations after multiplying by r² and deprojection. Center panel: high pass filtered image. Right panel: polar mapping from 0.1″ to 0.5″ of the sharper image in the center panel. The white lines show the spiral fit described in the text, and the shaded areas show the 3 σ uncertainty of the fit. In this case, the axis of the position angle is shifted in comparison with Fig. 2 for a better visualization of the fit.