The Red-Sequence Cluster Survey I: The Survey and Cluster Catalogs for Patches RCS0926+37 and RCS1327+29

The Red-Sequence Cluster Survey (RCS) is a $\sim$100 square degree, two-filter imaging survey in the $R_C$ and $z'$ filters, designed primarily to locate and characterise galaxy clusters to redshifts as high as $z=1.4$. This paper provides a detailed description of the survey strategy and execution, including a thorough discussion of the photometric and astrometric calibration of the survey data. The data are shown to be calibrated to a typical photometric uncertainty of 0.03-0.05 magnitudes, with total astrometric uncertainties less than 0.25 arcseconds for most objects. We also provide a detailed discussion of the adaptation of a previously described cluster search algorithm (the cluster red-sequence method) to the vagaries of real survey data, with particular attention to techniques for accounting for subtle variations in survey depths caused by changes in seeing and sky brightness and transparency. A first catalog of RCS clusters is also presented, for the survey patches RCS0926+37 and RCS1327+29. These catalogs, representing about 10% of the total survey and comprising a total of 429 candidate clusters and groups, contain a total of 67 cluster candidates at a photometric redshift of $0.9<z