GCN Circular 14592
D. A. Kann, B. Stecklum, and F. Ludwig (TLS Tautenburg) report: We observed the optical afterglow (Elenin et al., GCN 14450) of the nearby (Levan et al., GCN 14455), extremely bright GRB 130427A (Maselli et al., GCN 14448; Zhu et al., GCN 14471; von Kienlin, GCN 14473; Golenetskii et al., GCN 14487) with the 1.34m Schmidt telescope of the Thueringer Landessternwarte Tautenburg equipped with a 4k CCD camera under good weather conditions. We obtained 3 x 600 sec frames in the Rc band. The afterglow is detected in each frame. Using the nearby star given in Rumyantsev et al. (GCN 14582), we derive a preliminary magnitude of Rc = 20.27 +/- 0.07 at 8.55173 days after the GRB. This value is in good agreement with detections from the last few days (Kuroda et al., GCN 14534; Rumyantsev et al., GCN 14582). The afterglow does not yet show clear signs of flattening associated with either a rising supernova component or a significant contribution from the underlying host galaxy. This message may be cited.