Left: HST image of the QSO QSO 0153-0011, IAU name SDSS J015339.60-001104.8 located at z = 4.205. The field of view is 15 × 15 pixels. Center: we show the central region (3 × 3 pixels) reconstructed using the function F (Eq. (10)). We plot the cartesian axes centered on the maximum of the intensity pattern. Here ϵ = 0.23 and α = 0.14 rad. Each pixel of the analyzed area is divided into 15 × 15 sub-pixels. Right: we show the residuals of the central analyzed area (3 × 3 pixels).