We discuss two important consequences of recent experiments using surface plasmon polariton (SPP) tomography in a quantum eraser arrangement. In these experiments surface-emission images were modified by manipulating the polarization state of the leakage radiation. We show that SPP tomography does have the potential to produce images that mirror with high fidelity the propagation and interference of SPP beams at the metal-air interface of a sample. We reveal the physical mechanism behind this capability of SPP tomography. In addition, we show how SPP tomography can be used to detect photons passing through the dark fringes of an interference pattern and why photons propagate in such a way that looks like a photon can propagate across a region where it is never observed.