Rescaling of the images prior to obtaining bar stacks. Upper panel: image of NGC 4548 in magnitude scale with range 17−25 μ_{3.6 μm}(AB). The frame is aligned such that the y-axis points north and east is to the left. Axes are in units of arcsec. The blue dashed line corresponds to the visual measurement of the bar length and position angle from HE2015. The red dotted line corresponds to an ellipse of semi-major axis equal to 2 r_bar, whose PA and ellipticity are determined from the disk orientation parameters from P4. Lower panel: de-projected image of NGC 4548 reconstructed from the Fourier components in a polar grid on the disk plane. The image has been reoriented with respect to the bar major axis (PA_bar = 0), geometrically reflected across the bar major axis (to make the spiral arms wind clockwise), and resized to a grid of radius 3 times the bar size.