TITLE: GCN CIRCULAR NUMBER: 4627 SUBJECT: Erratum: SDSS pre-burst observations of GRB fields DATE: 06/02/01 16:08:43 GMT FROM: Richard J. Cool at U.of AZ/Steward Obs Richard J. Cool (University of Arizona) reports: Based upon feedback from users of our online releases of SDSS photometry and astrometry of GRB fields, we have discovered an error in several past releases. In preparing the releases, we inadvertently neglected to remove duplicate listings of several objects from the online catalogs. Several of the secondary observations of the objects included are of lower photometric quality than the primary observation and thus photometric zeropoints derived with them may shift slightly. We removed all duplicate observations from the online catalogs for past bursts located at http://mizar.as.arizona.edu/grb/public/. We apologize for any inconvenience.