  We present the first results from MOPSS, The Michigan Optical Planetary
Spectra Survey, aimed at creating a database of optical planetary transmission
spectra all observed, reduced, and analyzed with a uniform method for the
benefit of enabling comparative exoplanet studies. We discuss our methods, and
present results for our first two targets observed with the Magellan Baade 6.5m
telescope, one transit of the Hot Jupiter WASP-4b and two transits of the Hot
Saturn WASP-52b. Both targets present flat, featureless spectra, corresponding
to the presence of aerosols. We find that the cloud decks must begin no lower
than 10$^{-4}$ bar for both planets. For WASP-52b, we also consider the effects
of star spots on the transmission spectrum, including unocculted spots and
spots on the stellar limb influencing the light curve limb darkening
parameters. We discuss the usefulness of this program in the coming James Webb
Space Telescope era.
