TITLE: GCN CIRCULAR NUMBER: 18320 SUBJECT: GRB 150910A: Mt. Terskol observatory optical observations DATE: 15/09/16 11:45:10 GMT FROM: Alexei Pozanenko at IKI, Moscow A. Volnova (IKI), A. Sergeev (Terskol Branch of INASAN), M. Andreev (Terskol Branch of INASAN), E. Mazaeva (IKI), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration: We observed the field of GRB 150910A (Pagani et al., GCN 18264) with Zeiss-2000 telescope of Mt. Terskol observatory in R-filter starting on Sep. 11 (UT) 00:40:58. The afterglow (Pagani et al., GCN 18264; Zheng & Filippenko, GCN 18265) is clearly detected in a each image. The photometry of a combined image is following Date UT start t-T0 Filter Exp. OT Err (mid, days) (s) 2015-09-11 00:40:58 0.67083 R 13*120 20.90 0.07 The photometry is based on SDSS stars used in GCN 18281 (Mazaeva et al.)