B absolute magnitude plotted vs. redshift for all CNOC2 galaxies with ﹩R_{\mathrm{C}\,}\leq 21.5﹩ and ﹩0.12\leq z\leq 0.55﹩. The curved line gives the limit imposed by the limiting apparent magnitude, assuming the maximal k‐correction ﹩k^{\mathrm{max}\,}_{R_{\mathrm{C}\,}\rightarrow B}( z) ﹩ at redshift z. Note that objects lying below this line are brighter than ﹩R_{\mathrm{C}\,}=21.5﹩ but are blue; § 4.3 explains why these objects are excluded from the sample. The upper horizontal line indicates the bright limit imposed on the sample (﹩M^{k,e}_{B}=-21﹩), while the lower horizontal line denotes the faint limit (﹩M^{k,e}_{B}=-17﹩). Galaxies satisfying all of these criteria (and hence used in the calculation of N_c and L_c) are marked with triangles; the remainder are indicated with crosses.