Normalized histograms comparing a) apparent magnitude in the r band, b) redshift z, c) absolute magnitude in the r band, and d) galaxy colour g − r. The black filled histograms represent the entire Stripe 82 sample, while the SPRC+RM19 (see text) and our new candidates are shown as blue dashed and orange solid histograms, respectively. Plot e): a colour-magnitude diagram (the underlying density plot depicts the distribution of the entire Stripe 82 sample of the 18 362 galaxies). All magnitudes have been corrected for K-correction (Chilingarian et al. 2010; Chilingarian & Zolotukhin 2012) and Galactic extinction using the conversions from Schlafly & Finkbeiner (2011) applied to E(B − V) from Schlegel et al. (1998). Plot f): luminosity functions of our new PRG sample and the entire Stripe 82 sample calculated with Chołoniewski’s method (Choloniewski 1986).