GCN Circular 30614
V. Kim (FAI, Pulkovo Observatory), A. Pozanenko (IKI), M. Krugov (FAI), N. Pankov (HSE, IKI), S. Belkin (IKI) report on behalf of GRB IKI FuN: We observed the field of GRB 210610B (Lien et al., GCN 30600) with AZT-20 telescope of Assy-Turgen observatory starting on 2021-08-07 (UT) 20:45:22. We clearly detect the optical afterglow (Lien et al., GCN 30600; Hu et al., GCN 30602; Lipunov et al., GCN 30607). Preliminary photometry of the optical afterglow in a stacked image is following Date UT start t-T0 Exp. Filter OT Err. UL(3sigma) (mid, days) (s) 2021-08-07 20:45:22 0.47601 75*60 r' 21.28 0.05 23.6 The photometry is based on nearby PS1 stars.