The Local Group Stellar Populations Archive from the Hubble Space Telescope WFPC2

We present a database (LOGPHOT) of stellar photometry of Local Group galaxies obtained with the Hubble Space Telescope using the Wide Field Planetary Camera 2 (WFPC2). The database includes photometry from all WFPC2 observations taken through 2003 with long exposures (>500 s) in F555W and F814W, and many observations in which long exposures were taken in at least two broadband filters. We have attempted to derive and use techniques that produce the best photometry; the database has been fully populated using the HSTphot photometry package. To test the effects of different techniques, independent reductions were made for a few fields, and the comparison of these highlights some important issues and gives an estimate of plausible errors; these tests also led to some minor modifications and improvements to HSTphot. We provide both point-spread function photometry and subtracted-frame aperture photometry and discuss the merits of each. The database is available electronically. In addition to discussing the techniques used to construct the database, we present color-magnitude diagrams from single fields in each of the Local Group galaxies that have been observed; these provide an educational and visual display of the variety of star formation histories observed in Local Group galaxies.