Aerosols and other scatterers in planetary atmospheres polarize the sunlight reflected from the planet. Measurements of this polarization and its dependence on wavelength, phase angle and location on the planet provide important information that can be used to characterize the clouds and hazes in the atmosphere. However there are few observations that fully explore the available parameter space. Here we describe new observations obtained with a highly efficient imaging polarimeter on a small telescope that provides wide wavelength and phase coverage. Results are presented for a number of planets including Venus, Jupiter and Saturn. The different patterns of polarization vectors across the planet show the relative importance of single and multiple scattering and help to constrain the cloud particle properties.