GCN Circular 5181
V.Rumyantsev (CrAO), A. Pozanenko (IKI) on behalf of larger GRB follow up collaboration report: We observed optical transient of GRB060526 (Campana et al. GCN 5162, French & Jelinek GCN 5165, Rykoff et al. GCN 5166) with the Shajn 2.6m telescope of CrAO between May 27 (UT) 18:27 - 20:05 in R and B bands. In combined images we detect OT in R and do not detect it in B-band. The photometry of the OT and upper limits are following: Mid time Filter Exp. OT, mag. Limiting mag. (UT) sec May 27.803 R 18x60 20.25 +/-0.04 23.0 May 27.777 B 6x120 - 20.6 The photometry calibration is based on USNO A2.0 field stars. (We note that R magnitudes of field stars in USNO A2.0 are somewhat brighter (~0.2m) than those in USNO B1.0). The R-combined image can be found in http://grb.rssi.ru/GRB060526 This message may be cited.