Colour image of the OH absorption against a) the 50  km s^-1 cloud at 50  km s^-1, b) the CND at two channels integrated, namely −73 and 103  km s^-1, and c) the +20  km s^-1 cloud at 24  km s^-1with 7′′ × 5′′ resolution. Light blue colour indicates the deepest absorption. The contours delineate the OH absorption at 126′′ resolution, and the levels are 10, 20, 30, and 40 Jy/beam. The circle indicates the Odin beam position and size, the black cross shows the position of Sgr A^∗, and the white diagonal line is parallell to the Galactic plane.