Originally reduced image of MBH94 for NGC 5907, shown with a colour map that emphasizes the variations of the background field (their Fig. 1b). The unit of the axes is pixels. The galaxy centre position used is marked with an ×. Two sets of green circles indicate the distance at 100 and 150 px away from the two saturated stars 1 and 2. The positions of five bright stars (twelve regions that were used to measure the background) are indicated with markers and a number (circles and a character), cf. Table C.2 (Table C.1).