as an estimate for the photometric errors. The resulting errors in the $i$-band at a mean luminosity of $19\fm5$ for the various epochs range between $0\fm085$ for and $0\fm094$ for , respectively.

Near-infrared data
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$K_{s}$-band images taken with the NOTCam suffer from distortion that severely increases towards the edge of the frame. Thus, the frames had to be corrected for this effect before carrying out the standard image reduction steps. Glfalk ([@galfalk]) constructed a model of the NOTCamWF camera distortion based on his observations of B335. This NOTCam-model[^3] was implemented in a software provided by Glfalk ([@galfalk], written in IDL, which performs additional corrections), which was used for distortion correction of all $K_{s}$-band images. Subsequently, the usual reduction steps of near-IR imaging were applied to the dithered $K_{s}$-band images. All frames belonging to one quadrant were aligned and merged to one image to achieve a higher S/N. Point-spread functions fitting photometry was carried out using the DAOPHOT/ALLSTAR photometry package (Stetson & Harris [@stetson]). The photometric zero-points to calibrate $K_{s}$ were derived using constant stars in each quadrant of the target galaxy, which were also found in the 2MASS Point Source Catalogue (Cutri et al. [@cutri]). $K_s$-magnitudes of the detected 