  Since the earliest days of Heavy Ion Physics thermal soft photon radiation
emitted during the reaction had been theorized as a smoking gun signal for
formation of a quark-gluon plasma and as a tool to characterize its properties.
In recent years the existence of excess photon radiation in heavy ion
collisions over the expectation from initial hard interactions has been
confirmed at both RHIC and LHC energies by PHENIX and ALICE respectively. There
the radiation has been found to exhibit elliptic flow $v_2$ well above what can
currently be reconciled with a picture of early emission from a plasma phase.
During the 2007 and 2010 Au+Au runs PHENIX has measured a high purity sample of
soft photons down to $p_T>0.4\,\text{GeV}/c$ using an external conversion
method. We present recent systematic studies by PHENIX from that sample on the
centrality dependence of the soft photon yield, and elliptic and triangular
flow $v_2$ and $v_3$ in Au+Au collisions which fill in the experimental picture
and enable discrimination of competing soft photon production scenarios.
