TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3771 SUBJECT: GRB 050805b: OHP optical limits DATE: 05/08/05 23:59:29 GMT FROM: Alain Klotz at CESR-CNRS Damerdji, Y. (CESR-OMP/OHP), Klotz, A. (CESR-OMP), Boer M. (OHP), Atteia J.L. (LATT-OMP) report: We imaged the field of GRB 050805b detected by SWIFT (trigger 149131) with the 0.8m (F/15) telescope located at the Observatoire de Haute Provence Observatory (OHP), France. Camera is an Andor 47-40 equiped by a R band filter. First image was begined 16.4 min after the GRB. Weather conditions were excellents. We detected no new source comparing our succesive frames. From the first frame we give an limit: TMid(min since GRB) Exp(s) R-mag 18.87 300 >20.3 Limiting magnitude was estimated with the nearby USNO-B1 stars. This message can be cited.