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The galaxy population observed near cosmic noon (at redshift z=1-2) shows numerous differences from that in the nearby universe. Since we have only been able to study the integrated light of galaxies at z=1-2 comma however comma we do not know whether their luminous stellar populations comma which drive galaxy evolution comma may also be distinct. Separately comma the constituents of dark matter remain unidentified comma and current limits would allow a small population of primordial black holes (PBHs) formed during inflation. The Hubble Space Telescope has recently been used to find individual comma luminous stars at z=1-2 that are highly magnified by foreground galaxy clusters. As a background magnified star becomes aligned with a star or remnant in the foreground cluster comma its magnification and apparent brightness can change. Using the same stellar population synthesis models that are applied to interpret galaxies at z=1-2 comma we find that the observed microlensing events are both brighter and more numerous than expected. PBHs responsible for 1-2% of dark matter could explain the events comma while revised stellar evolution models with additional blue supergiants (BSGs) comma which match the photometry of two lensed stars comma may present an alternative. Here we propose a SNAP program to image cluster fields that contain blue comma bright giant arcs having luminous stars close the galaxy cluster.s critical curve. The survey will be able to distinguish between PBHs accounting for 2% of dark matter comma and an excess of luminous BSGs comma some of which should always be detectable (<28 mag). We will be able to provide targets for James Webb Space Telescope spectroscopy and draw comparisons with nearby luminous stellar populations.