GCN Circular 5510
A. de Ugarte Postigo (IAA-CSIC Granada), J.French (UCD Dublin) and P.Kubanek (AsU AV CR Ondrejov & ISDC Versoix) reports on behalf of the Watcher collaboration: The 0.4m Watcher telescope, located at Boyden Observatory, South Africa, observed the SWIFT error box for GRB 060904B (Grupe et al. GCN 5505) starting at 02:32:05 UT observing in R, V, I bands + unfiltered. We detect the optical counterpart at coordinates reported by Rykoff et al. (GCN 5504), with peak brightness unfiltered 17.1+/-0.3 at 02:39:30 UT, consistent with Tarot peak detection (Klotz et al. GCN 5508). This message is quotable.