TITLE: GCN CIRCULAR NUMBER: 22205 SUBJECT: GRB 171205A: TSHAO optical observations DATE: 17/12/07 19:30:56 GMT FROM: Alexei Pozanenko at IKI, Moscow A. Volnova (IKI), A. Pozanenko (IKI), E. Mazaeva (IKI), M. Krugov (FAPHI), I. Reva (FAPHI), A. Kusakin (FAPHI), report on behalf of larger GRB follow-up collaboration: We observed the field of GRB 171205A (D'Elia et al., GCN 22177) with Zeiss-1000 1-m telescope of Tien Shan Astronomical Observatory starting on Dec. 06 (UT) 22:2319. We took several images in R-filter. The afterglow of GRB 171205A (Izzo et al. GCN 22180; Emery et al. GCN 22181; Butler et al. GCN 22182; Mao et al. GCN 22186; Choi et al. GCN 22188; Melandri et al. GCN 22189; Steeghs et al. GCN 22190; Cobb et al. GCN 22192; Volnova et al. GCN 22193; Guidorzi et al. GCN 22197; Schmidl et al. GCN 22198; Lipunov et al. GCN 22199; Ugarte Postigo et al. GCN 22204) is marginally detected. Preliminary photometry is following. Date UT start t-T0 Filter Exp. OT Err. (mid, days) (s) 2017-12-06 22:23:19 1.63574 R 1500 20.4 0.3 The photometry is based on several nearby USNO-B1.0 stars previously used in GCN 22193.