TITLE: GCN CIRCULAR NUMBER: 19986 SUBJECT: GRB 161004A: SAO RAS optical upper limit DATE: 16/10/04 23:02:45 GMT FROM: Moskvitin Alexander at SAO RAS A. Moskvitin (SAO RAS), A. Volnova (IKI), and A. Pozanenko (IKI) report on behalf of the larger GRB follow-up team. We observed the field of GRB 161004A (Evans et al., GCN 19979) with Zeiss-1000 - the 1-meter telescope of Special Astrophysical Observatory of Russian Academy of Sciences. We obtain several images with filter Rc starting on October, 4 (UT) 15:44:35. In the refined XRT error circle (Beardmore et al., GCN 19983) we do not detect the optical counterpart (Breeveld and Evans, GCN 19984). Preliminary photometry of a combined image is following Date UT start t-T0 Filter Exp. OT UL (mid, days) (s) 2016-10-04 15:44:35 0.1396 Rc 12*300 n/d 22.4 Photometry is based on nearby SDSS-DR9 stars reported by Mazaeva et al. (GCN 19980).