  We revisit old ideas that smearing or blocking an SU(N) lattice gauge field,
or averaging over an ensemble of fields created in the neighbourhood of that
field, can reduce the high frequency fluctuations sufficiently that the naive
lattice operator for the topological charge density is able to provide a
reliable measure of the topological charge of the field. We show that these
three methods do indeed provide additional simple methods for calculating the
total topological charge, with smearing particularly economical at current
couplings. More interestingly, the ensemble average method can also be used to
expose the distribution in space-time of the topological charge and this
conceptually transparent, albeit computationally expensive, method provides a
useful benchmark against which to compare other methods. Using this benchmark
we find that a few smearing steps are also reliable in exposing the
distribution in space-time of the topological charge, thus providing a very
economical and simple method for doing so. We also use the same benchmark to
determine what is the number of `cooling' sweeps one needs to perform in order
to expose the charge density reliably.
