1999MNRAS.304..311M

An automated search for low-surface-brightness (LSB) galaxies over 2187 deg² of sky produced 2435 galaxies. The technique, calibration, background contamination, models of the galaxy populations, survey and catalogue were discussed in Paper I. In this paper we present an analysis of our results. The number density of Fornax LSB galaxies drops exponentially with radius from the cluster centre with a scalelength of 1.25° while the bright galaxies have a scalelength of 0.48°. Spectroscopic observations in the Fornax region reveal that two LSB galaxies are at approximately the same redshift as the Fornax cluster, yet they are six bright galaxy scalelengths from the cluster centre. A correlation analysis of the sample indicates that our galaxies are much more strongly clustered (A_ω =0.82) than the general faint population (at the same magnitude limit) but less so than the bright nearby RC3 galaxies (A_ω = 2.23) sampled within the same volume. This implies that LSB galaxies are associated with bright galaxies, but distributed over a larger scale. We have compared our observations with a fading model of the faint galaxy number counts. This model predicts ~60 galaxies per field while we detect on average 13. Either the fading models are incorrect or there is strong differential fading between clusters and field. The luminosity function of the Fornax cluster has a slope of α =-1.58±0.6. The total luminosity of the Fornax cluster is dominated by bright galaxies with a LSB-to-bright luminosity ratio of 0.02 while the field has a ratio of 0.03.