A newly proposed gravity theory suggests that, in addition to mass, electromagnetic (EM) waves—or photons—can generate gravitational forces. The theory introduces two governing equations: one describing gravity between photons, and another describing gravity between a photon and a massive object, with force proportional to photon frequency. This frequency dependence implies that light should bend differently depending on its wavelength when passing near a massive body, potentially producing a dispersion in strong gravitational lensing. In contrast, Einstein's general relativity predicts frequency-independent light bending, producing sharp-edged gravitationally lensed images even for broadband (white light) sources. Observationally, most gravitationally lensed images exhibit fringe-like edges, suggesting possible frequency/wavelength-dependent bending. Such optical phenomena, specifically gravitational lensing fringes, may serve as a discriminant between general relativity and electromagnetic gravity theories.