  The redshift-luminosity distributions for well-defined galaxies and quasars
in the Sloan Digital Sky Survey (SDSS) are compared for the two
redshift-distance relations of a Hubble redshift and a de Sitter redshift.
Assuming a Hubble redshift, SDSS data can be interpreted as luminosity
evolution following the Big Bang. In contrast, given a de Sitter redshift, the
intrinsic brightness of objects at all redshifts is roughly the same. In a de
Sitter universe, 95 per cent of SDSS galaxies and quasars fall into a magnitude
range of only 2.8, and 99.7 per cent are within 5.4 mag. The comparable Hubble
luminosity ranges are much larger: 95 per cent within 6.9, and 99.7 per cent
within 11.5 mag. De Sitter space is now widely discussed, but the de Sitter
redshift is hardly mentioned.
