TITLE: GCN CIRCULAR NUMBER: 32809 SUBJECT: GRB221009A: LBT optical imaging DATE: 22/10/20 15:24:03 GMT FROM: Andrea Rossi at INAF A. Rossi, E. Maiorano (INAF-OAS), D. B. Malesani (Radboud Univ. and DAWN/NBI)on behalf of the CIBO collaboration, F. Cusano (INAF-OAS), and D. Paris (INAF-OA Roma), report: We observed the field of GRB 221009A (Dichiara et al., GCN 32632; Kennea & Williams, GCN 32635; Veres et al., GCN 32636; Bissaldi et al., GCN 32637; Svinkin et al., GCN 32641; Ursi et al., GCN Circ. 32650) simultaneously in the blue and red arms with the g'+r' and g'+i' bands with the MODS instrument mounted on LBT (Mt Graham, AZ, USA). We observed for 22 min per arm at the midtime 03:11 UT on 2022-10-18, 8.58 days after the burst trigger. Observations were performed under modest weather conditions with an average seeing of ~1" but high humidity and passing cirrus. We clearly detect the afterglow and we preliminary measure r=21.63+-0.02 (AB system), calibrated against Pan-STARRS field stars. We acknowledge the excellent support from the LBTO and LBT-INAF staff, particularly A. Becker and D. G. Huerta in obtaining these observations.