Top: distribution of TRGB magnitudes for each region of the inner (squares) and outer (triangles) annuli (Fig. 18) plotted against azimuthal angle. Bottom: TRGB magnitude measured in each of the 4 equally spaced annuli described previously plotted as a function of distance from the galactic centre. A weighted linear fit has been made to all the data points (solid black line) and to only those points within 3 kpc of the centre (dashed red line).