A Medium-Deep Survey of a Mini-Slice at the North Galactic Pole. II. The   Data
  We report 328 redshifts, b$_J$ magnitudes and b$_J$--r$_F$ colors of galaxies measured in a redshift survey of a 4$^\circ$ $\times$ 0.67$^\circ$ slice close to the north Galactic pole. The faintest galaxies in this survey have a magnitude of b$_J$ $\sim$ 20.5. The redshifts present external errors of the order of 70 \kms, and we estimate that the mean photometry errors are $\sim$ 0.2 for magnitudes and $\sim$ 0.3 for colors. The redshift completeness level of the sample is of the order of $\sim$ 35\% at b$_J$=20, and part of this rather low completeness is the result of the combination of limitations imposed by the multifiber system with the clustering of galaxies, and an insufficient number of configurations. At the nominal magnitude limit of the survey, we were able to measure redshifts for $\sim$ 70 \% of the galaxies we observed. From the correlation between observed properties of the galaxies in this sample, we demonstrate that the mean surface brightness is a major limiting factor in our ability to measure redshifts of faint objects. 
C.N.A. Willmer, D.C. Koo, N. ELlman, M.J. Kurtz, and A.S. Szalay