  Spin-observables in pseudoscalar meson photoproduction is discussed. This
work is complementary to the earlier works on this topic. Here, the reaction
amplitude is expressed in Pauli-spin basis which allows to calculate all the
observables straightforwardly. We make use of the fact that the underlying
reflection symmetry about the reaction plane can be most conveniently and
easily exploited in this basis to help finding the non-vanishing and
independent observables in this reaction. The important issue of complete
experiments is reviewed. By expressing the reaction amplitude in Pauli-spin
basis, many sets of eight observables - distinct from those found in earlier
works from the amplitude in transversity basis - capable of determining the
reaction amplitude up to an overall phase are found. It is also shown that some
of the combinations of the spin observables are suited for studying certain
aspects of the reaction dynamics. We, then, carry out a (strictly)
model-independent partial-wave analysis, in particular, of the peculiar angular
behavior of the beam asymmetry observed in eta' photoproduction very close to
threshold [P. Levi Sandri et al. 2015 Eur. Phys. J. A 51, 77]. This work should
be useful, especially, for newcomers in the field of baryon spectroscopy, where
the photoproduction reactions are a major tool for probing the baryon spectra.
