  The Sloan Digital Sky Survey has provided spectra of a large number of new PG
1159 stars and DO white dwarfs. This increase in known hot H-deficient compact
objects significantly improves the statistics and helps to investigate late
stages of stellar evolution. We have finished our analyses of nine PG 1159
stars and 23 DO white dwarfs by means of detailed NLTE model atmospheres. From
the optical SDSS spectra, effective temperatures, surface gravities, and
element abundances are derived by using our new automated chi^2-fitting in
order to place the observed objects in an evolutionary context. Especially the
connection between PG 1159 stars and DO white dwarfs has been investigated.
