The Hong-Ou-Mandel (HOM) effect is a direct consequence of the bosonic nature of photons [1], as such, it occurs maximally in the presence of truly indistinguishable photons. Measuring the magnitude of the HOM effect is required to determine the reliability with which a photon source is able to produce indistinguishable photons. Using this method, single photon sources have shown the ability to provide photons with remarkable levels of indistinguishability [2].