Multicolor photometry of the J0053+1234 field. ﹩U-B﹩ vs. ﹩B-R﹩ color‐color plot for the 1552 sources with UBRI photometry. The photometry presented here has been corrected for air mass and color terms, as well as Galactic extinction using the Schlegel et al. (1998) reddening maps. The average systematic color errors, which dominate over random photometric errors, are given in the lower left box. There are 44 spectroscopically confirmed quasars (filled triangles) and 48 confirmed non‐quasistellar objects (open triangles). The boundary (dashed line) represents the estimated end of the stellar locus; therefore, sources bluer than this are likely quasars (see text for details).