Morphology of the central elliptical. Upper left: R band image, upper right: isophote map, lower left: R band image after subtraction of the median box filter, lower right: residuals to the IRAF ellipse model. Shells are clearly visible in the lower panels and show strong symmetry along the major axis. The isophote map reveals boxy isophotes in the outer regions of the galaxy, resulting from the observed shell structure. The residuals illustrate the large contamination of foreground sources which have been masked within the ellipse task. The field of view is  ~1.5 arcmin on a side in the left panels and  ~2.2 arcmin in the right ones.